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Diffstat (limited to 'src/contrib/libngtcp2/ngtcp2/ngtcp2.h')
-rw-r--r-- | src/contrib/libngtcp2/ngtcp2/ngtcp2.h | 5906 |
1 files changed, 5906 insertions, 0 deletions
diff --git a/src/contrib/libngtcp2/ngtcp2/ngtcp2.h b/src/contrib/libngtcp2/ngtcp2/ngtcp2.h new file mode 100644 index 0000000..d4ba09d --- /dev/null +++ b/src/contrib/libngtcp2/ngtcp2/ngtcp2.h @@ -0,0 +1,5906 @@ +/* + * ngtcp2 + * + * Copyright (c) 2017 ngtcp2 contributors + * Copyright (c) 2017 nghttp2 contributors + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +#ifndef NGTCP2_H +#define NGTCP2_H + +/* Define WIN32 when build target is Win32 API (borrowed from + libcurl) */ +#if (defined(_WIN32) || defined(__WIN32__)) && !defined(WIN32) +# define WIN32 +#endif + +#ifdef _MSC_VER +# pragma warning(push) +# pragma warning(disable : 4324) +#endif + +#include <stdlib.h> +#if defined(_MSC_VER) && (_MSC_VER < 1800) +/* MSVC < 2013 does not have inttypes.h because it is not C99 + compliant. See compiler macros and version number in + https://sourceforge.net/p/predef/wiki/Compilers/ */ +# include <stdint.h> +#else /* !defined(_MSC_VER) || (_MSC_VER >= 1800) */ +# include <inttypes.h> +#endif /* !defined(_MSC_VER) || (_MSC_VER >= 1800) */ +#include <sys/types.h> +#include <stdarg.h> +#include <stddef.h> + +#ifndef NGTCP2_USE_GENERIC_SOCKADDR +# ifdef WIN32 +# ifndef WIN32_LEAN_AND_MEAN +# define WIN32_LEAN_AND_MEAN +# endif +# include <ws2tcpip.h> +# else +# include <sys/socket.h> +# include <netinet/in.h> +# endif +#endif + +#ifdef AF_INET +# define NGTCP2_AF_INET AF_INET +#else +# define NGTCP2_AF_INET 2 +#endif + +#ifdef AF_INET6 +# define NGTCP2_AF_INET6 AF_INET6 +#else +# define NGTCP2_AF_INET6 23 +# define NGTCP2_USE_GENERIC_IPV6_SOCKADDR +#endif + +#include <ngtcp2/version.h> + +#ifdef NGTCP2_STATICLIB +# define NGTCP2_EXTERN +#elif defined(WIN32) +# ifdef BUILDING_NGTCP2 +# define NGTCP2_EXTERN __declspec(dllexport) +# else /* !BUILDING_NGTCP2 */ +# define NGTCP2_EXTERN __declspec(dllimport) +# endif /* !BUILDING_NGTCP2 */ +#else /* !defined(WIN32) */ +# ifdef BUILDING_NGTCP2 +# define NGTCP2_EXTERN __attribute__((visibility("default"))) +# else /* !BUILDING_NGTCP2 */ +# define NGTCP2_EXTERN +# endif /* !BUILDING_NGTCP2 */ +#endif /* !defined(WIN32) */ + +#ifdef _MSC_VER +# define NGTCP2_ALIGN(N) __declspec(align(N)) +#else /* !_MSC_VER */ +# define NGTCP2_ALIGN(N) __attribute__((aligned(N))) +#endif /* !_MSC_VER */ + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * @typedef + * + * :type:`ngtcp2_ssize` is signed counterpart of size_t. + */ +typedef ptrdiff_t ngtcp2_ssize; + +/** + * @functypedef + * + * :type:`ngtcp2_malloc` is a custom memory allocator to replace + * :manpage:`malloc(3)`. The |user_data| is + * :member:`ngtcp2_mem.user_data`. + */ +typedef void *(*ngtcp2_malloc)(size_t size, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_free` is a custom memory allocator to replace + * :manpage:`free(3)`. The |user_data| is + * :member:`ngtcp2_mem.user_data`. + */ +typedef void (*ngtcp2_free)(void *ptr, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_calloc` is a custom memory allocator to replace + * :manpage:`calloc(3)`. The |user_data| is the + * :member:`ngtcp2_mem.user_data`. + */ +typedef void *(*ngtcp2_calloc)(size_t nmemb, size_t size, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_realloc` is a custom memory allocator to replace + * :manpage:`realloc(3)`. The |user_data| is the + * :member:`ngtcp2_mem.user_data`. + */ +typedef void *(*ngtcp2_realloc)(void *ptr, size_t size, void *user_data); + +/** + * @struct + * + * :type:`ngtcp2_mem` is a custom memory allocator. The + * :member:`user_data` field is passed to each allocator function. + * This can be used, for example, to achieve per-connection memory + * pool. + * + * In the following example code, ``my_malloc``, ``my_free``, + * ``my_calloc`` and ``my_realloc`` are the replacement of the + * standard allocators :manpage:`malloc(3)`, :manpage:`free(3)`, + * :manpage:`calloc(3)` and :manpage:`realloc(3)` respectively:: + * + * void *my_malloc_cb(size_t size, void *user_data) { + * (void)user_data; + * return my_malloc(size); + * } + * + * void my_free_cb(void *ptr, void *user_data) { + * (void)user_data; + * my_free(ptr); + * } + * + * void *my_calloc_cb(size_t nmemb, size_t size, void *user_data) { + * (void)user_data; + * return my_calloc(nmemb, size); + * } + * + * void *my_realloc_cb(void *ptr, size_t size, void *user_data) { + * (void)user_data; + * return my_realloc(ptr, size); + * } + * + * void conn_new() { + * ngtcp2_mem mem = {NULL, my_malloc_cb, my_free_cb, my_calloc_cb, + * my_realloc_cb}; + * + * ... + * } + */ +typedef struct ngtcp2_mem { + /** + * :member:`user_data` is an arbitrary user supplied data. This + * is passed to each allocator function. + */ + void *user_data; + /** + * :member:`malloc` is a custom allocator function to replace + * :manpage:`malloc(3)`. + */ + ngtcp2_malloc malloc; + /** + * :member:`free` is a custom allocator function to replace + * :manpage:`free(3)`. + */ + ngtcp2_free free; + /** + * :member:`calloc` is a custom allocator function to replace + * :manpage:`calloc(3)`. + */ + ngtcp2_calloc calloc; + /** + * :member:`realloc` is a custom allocator function to replace + * :manpage:`realloc(3)`. + */ + ngtcp2_realloc realloc; +} ngtcp2_mem; + +/** + * @macrosection + * + * Time related macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_SECONDS` is a count of tick which corresponds to 1 second. + */ +#define NGTCP2_SECONDS ((ngtcp2_duration)1000000000ULL) + +/** + * @macro + * + * :macro:`NGTCP2_MILLISECONDS` is a count of tick which corresponds + * to 1 millisecond. + */ +#define NGTCP2_MILLISECONDS ((ngtcp2_duration)1000000ULL) + +/** + * @macro + * + * :macro:`NGTCP2_MICROSECONDS` is a count of tick which corresponds + * to 1 microsecond. + */ +#define NGTCP2_MICROSECONDS ((ngtcp2_duration)1000ULL) + +/** + * @macro + * + * :macro:`NGTCP2_NANOSECONDS` is a count of tick which corresponds to + * 1 nanosecond. + */ +#define NGTCP2_NANOSECONDS ((ngtcp2_duration)1ULL) + +/** + * @macrosection + * + * QUIC protocol version macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_PROTO_VER_V1` is the QUIC version 1. + */ +#define NGTCP2_PROTO_VER_V1 ((uint32_t)0x00000001u) + +/** + * @macro + * + * :macro:`NGTCP2_PROTO_VER_V2` is the QUIC version 2. + * + * https://quicwg.org/quic-v2/draft-ietf-quic-v2.html + */ +#define NGTCP2_PROTO_VER_V2 ((uint32_t)0x6b3343cfu) + +/** + * @macro + * + * :macro:`NGTCP2_PROTO_VER_DRAFT_MAX` is the maximum QUIC draft + * version that this library supports. + */ +#define NGTCP2_PROTO_VER_DRAFT_MAX 0xff000020u + +/** + * @macro + * + * :macro:`NGTCP2_PROTO_VER_DRAFT_MIN` is the minimum QUIC draft + * version that this library supports. + */ +#define NGTCP2_PROTO_VER_DRAFT_MIN 0xff00001du + +/** + * @macro + * + * :macro:`NGTCP2_PROTO_VER_MAX` is the highest QUIC version that this + * library supports. + */ +#define NGTCP2_PROTO_VER_MAX NGTCP2_PROTO_VER_V1 + +/** + * @macro + * + * :macro:`NGTCP2_PROTO_VER_MIN` is the lowest QUIC version that this + * library supports. + */ +#define NGTCP2_PROTO_VER_MIN NGTCP2_PROTO_VER_DRAFT_MIN + +/** + * @macro + * + * :macro:`NGTCP2_RESERVED_VERSION_MASK` is the bit mask of reserved + * version. + */ +#define NGTCP2_RESERVED_VERSION_MASK 0x0a0a0a0au + +/** + * @macrosection + * + * UDP datagram related macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_MAX_UDP_PAYLOAD_SIZE` is the default maximum UDP + * datagram payload size that this endpoint transmits. + */ +#define NGTCP2_MAX_UDP_PAYLOAD_SIZE 1200 + +/** + * @macro + * + * :macro:`NGTCP2_MAX_PMTUD_UDP_PAYLOAD_SIZE` is the maximum UDP + * datagram payload size that Path MTU Discovery can discover. + */ +#define NGTCP2_MAX_PMTUD_UDP_PAYLOAD_SIZE 1452 + +/** + * @macrosection + * + * QUIC specific macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_MAX_VARINT` is the maximum value which can be + * encoded in variable-length integer encoding. + */ +#define NGTCP2_MAX_VARINT ((1ULL << 62) - 1) + +/** + * @macro + * + * :macro:`NGTCP2_STATELESS_RESET_TOKENLEN` is the length of Stateless + * Reset Token. + */ +#define NGTCP2_STATELESS_RESET_TOKENLEN 16 + +/** + * @macro + * + * :macro:`NGTCP2_MIN_STATELESS_RESET_RANDLEN` is the minimum length + * of random bytes (Unpredictable Bits) in Stateless Reset packet + */ +#define NGTCP2_MIN_STATELESS_RESET_RANDLEN 5 + +/** + * @macro + * + * :macro:`NGTCP2_PATH_CHALLENGE_DATALEN` is the length of + * PATH_CHALLENGE data. + */ +#define NGTCP2_PATH_CHALLENGE_DATALEN 8 + +/** + * @macro + * + * :macro:`NGTCP2_RETRY_KEY_DRAFT` is an encryption key to create + * integrity tag of Retry packet. It is used for QUIC draft versions. + */ +#define NGTCP2_RETRY_KEY_DRAFT \ + "\xcc\xce\x18\x7e\xd0\x9a\x09\xd0\x57\x28\x15\x5a\x6c\xb9\x6b\xe1" + +/** + * @macro + * + * :macro:`NGTCP2_RETRY_NONCE_DRAFT` is nonce used when generating + * integrity tag of Retry packet. It is used for QUIC draft versions. + */ +#define NGTCP2_RETRY_NONCE_DRAFT \ + "\xe5\x49\x30\xf9\x7f\x21\x36\xf0\x53\x0a\x8c\x1c" + +/** + * @macro + * + * :macro:`NGTCP2_RETRY_KEY_V1` is an encryption key to create + * integrity tag of Retry packet. It is used for QUIC v1. + */ +#define NGTCP2_RETRY_KEY_V1 \ + "\xbe\x0c\x69\x0b\x9f\x66\x57\x5a\x1d\x76\x6b\x54\xe3\x68\xc8\x4e" + +/** + * @macro + * + * :macro:`NGTCP2_RETRY_NONCE_V1` is nonce used when generating integrity + * tag of Retry packet. It is used for QUIC v1. + */ +#define NGTCP2_RETRY_NONCE_V1 "\x46\x15\x99\xd3\x5d\x63\x2b\xf2\x23\x98\x25\xbb" + +/** + * @macro + * + * :macro:`NGTCP2_RETRY_KEY_V2` is an encryption key to create + * integrity tag of Retry packet. It is used for QUIC v2. + * + * https://quicwg.org/quic-v2/draft-ietf-quic-v2.html + */ +#define NGTCP2_RETRY_KEY_V2 \ + "\x8f\xb4\xb0\x1b\x56\xac\x48\xe2\x60\xfb\xcb\xce\xad\x7c\xcc\x92" + +/** + * @macro + * + * :macro:`NGTCP2_RETRY_NONCE_V2` is nonce used when generating + * integrity tag of Retry packet. It is used for QUIC v2. + * + * https://quicwg.org/quic-v2/draft-ietf-quic-v2.html + */ +#define NGTCP2_RETRY_NONCE_V2 "\xd8\x69\x69\xbc\x2d\x7c\x6d\x99\x90\xef\xb0\x4a" + +/** + * @macro + * + * :macro:`NGTCP2_HP_MASKLEN` is the length of header protection mask. + */ +#define NGTCP2_HP_MASKLEN 5 + +/** + * @macro + * + * :macro:`NGTCP2_HP_SAMPLELEN` is the number bytes sampled when + * encrypting a packet header. + */ +#define NGTCP2_HP_SAMPLELEN 16 + +/** + * @macro + * + * :macro:`NGTCP2_DEFAULT_INITIAL_RTT` is a default initial RTT. + */ +#define NGTCP2_DEFAULT_INITIAL_RTT (333 * NGTCP2_MILLISECONDS) + +/** + * @macro + * + * :macro:`NGTCP2_MAX_CIDLEN` is the maximum length of Connection ID. + */ +#define NGTCP2_MAX_CIDLEN 20 + +/** + * @macro + * + * :macro:`NGTCP2_MIN_CIDLEN` is the minimum length of Connection ID. + */ +#define NGTCP2_MIN_CIDLEN 1 + +/** + * @macro + * + * :macro:`NGTCP2_MIN_INITIAL_DCIDLEN` is the minimum length of + * Destination Connection ID in Client Initial packet if it does not + * bear token from Retry packet. + */ +#define NGTCP2_MIN_INITIAL_DCIDLEN 8 + +/** + * @macro + * + * :macro:`NGTCP2_DEFAULT_HANDSHAKE_TIMEOUT` is the default handshake + * timeout. + */ +#define NGTCP2_DEFAULT_HANDSHAKE_TIMEOUT (10 * NGTCP2_SECONDS) + +/** + * @macrosection + * + * ECN related macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_ECN_NOT_ECT` indicates no ECN marking. + */ +#define NGTCP2_ECN_NOT_ECT 0x0 + +/** + * @macro + * + * :macro:`NGTCP2_ECN_ECT_1` is ECT(1) codepoint. + */ +#define NGTCP2_ECN_ECT_1 0x1 + +/** + * @macro + * + * :macro:`NGTCP2_ECN_ECT_0` is ECT(0) codepoint. + */ +#define NGTCP2_ECN_ECT_0 0x2 + +/** + * @macro + * + * :macro:`NGTCP2_ECN_CE` is CE codepoint. + */ +#define NGTCP2_ECN_CE 0x3 + +/** + * @macro + * + * :macro:`NGTCP2_ECN_MASK` is a bit mask to get ECN marking. + */ +#define NGTCP2_ECN_MASK 0x3 + +#define NGTCP2_PKT_INFO_VERSION_V1 1 +#define NGTCP2_PKT_INFO_VERSION NGTCP2_PKT_INFO_VERSION_V1 + +/** + * @struct + * + * :type:`ngtcp2_pkt_info` is a packet metadata. + */ +typedef struct NGTCP2_ALIGN(8) ngtcp2_pkt_info { + /** + * :member:`ecn` is ECN marking and when passing + * `ngtcp2_conn_read_pkt()`, and it should be either + * :macro:`NGTCP2_ECN_NOT_ECT`, :macro:`NGTCP2_ECN_ECT_1`, + * :macro:`NGTCP2_ECN_ECT_0`, or :macro:`NGTCP2_ECN_CE`. + */ + uint32_t ecn; +} ngtcp2_pkt_info; + +/** + * @macrosection + * + * ngtcp2 library error codes + */ + +/** + * @macro + * + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` indicates that a passed + * argument is invalid. + */ +#define NGTCP2_ERR_INVALID_ARGUMENT -201 +/** + * @macro + * + * :macro:`NGTCP2_ERR_NOBUF` indicates that a provided buffer does not + * have enough space to store data. + */ +#define NGTCP2_ERR_NOBUF -203 +/** + * @macro + * + * :macro:`NGTCP2_ERR_PROTO` indicates a general protocol error. + */ +#define NGTCP2_ERR_PROTO -205 +/** + * @macro + * + * :macro:`NGTCP2_ERR_INVALID_STATE` indicates that a requested + * operation is not allowed at the current connection state. + */ +#define NGTCP2_ERR_INVALID_STATE -206 +/** + * @macro + * + * :macro:`NGTCP2_ERR_ACK_FRAME` indicates that an invalid ACK frame + * is received. + */ +#define NGTCP2_ERR_ACK_FRAME -207 +/** + * @macro + * + * :macro:`NGTCP2_ERR_STREAM_ID_BLOCKED` indicates that there is no + * spare stream ID available. + */ +#define NGTCP2_ERR_STREAM_ID_BLOCKED -208 +/** + * @macro + * + * :macro:`NGTCP2_ERR_STREAM_IN_USE` indicates that a stream ID is + * already in use. + */ +#define NGTCP2_ERR_STREAM_IN_USE -209 +/** + * @macro + * + * :macro:`NGTCP2_ERR_STREAM_DATA_BLOCKED` indicates that stream data + * cannot be sent because of flow control. + */ +#define NGTCP2_ERR_STREAM_DATA_BLOCKED -210 +/** + * @macro + * + * :macro:`NGTCP2_ERR_FLOW_CONTROL` indicates flow control error. + */ +#define NGTCP2_ERR_FLOW_CONTROL -211 +/** + * @macro + * + * :macro:`NGTCP2_ERR_CONNECTION_ID_LIMIT` indicates that the number + * of received Connection ID exceeds acceptable limit. + */ +#define NGTCP2_ERR_CONNECTION_ID_LIMIT -212 +/** + * @macro + * + * :macro:`NGTCP2_ERR_STREAM_LIMIT` indicates that a remote endpoint + * opens more streams that is permitted. + */ +#define NGTCP2_ERR_STREAM_LIMIT -213 +/** + * @macro + * + * :macro:`NGTCP2_ERR_FINAL_SIZE` indicates that inconsistent final + * size of a stream. + */ +#define NGTCP2_ERR_FINAL_SIZE -214 +/** + * @macro + * + * :macro:`NGTCP2_ERR_CRYPTO` indicates crypto (TLS) related error. + */ +#define NGTCP2_ERR_CRYPTO -215 +/** + * @macro + * + * :macro:`NGTCP2_ERR_PKT_NUM_EXHAUSTED` indicates that packet number + * is exhausted. + */ +#define NGTCP2_ERR_PKT_NUM_EXHAUSTED -216 +/** + * @macro + * + * :macro:`NGTCP2_ERR_REQUIRED_TRANSPORT_PARAM` indicates that a + * required transport parameter is missing. + */ +#define NGTCP2_ERR_REQUIRED_TRANSPORT_PARAM -217 +/** + * @macro + * + * :macro:`NGTCP2_ERR_MALFORMED_TRANSPORT_PARAM` indicates that a + * transport parameter is malformed. + */ +#define NGTCP2_ERR_MALFORMED_TRANSPORT_PARAM -218 +/** + * @macro + * + * :macro:`NGTCP2_ERR_FRAME_ENCODING` indicates there is an error in + * frame encoding. + */ +#define NGTCP2_ERR_FRAME_ENCODING -219 +/** + * @macro + * + * :macro:`NGTCP2_ERR_DECRYPT` indicates a decryption failure. + */ +#define NGTCP2_ERR_DECRYPT -220 +/** + * @macro + * + * :macro:`NGTCP2_ERR_STREAM_SHUT_WR` indicates no more data can be + * sent to a stream. + */ +#define NGTCP2_ERR_STREAM_SHUT_WR -221 +/** + * @macro + * + * :macro:`NGTCP2_ERR_STREAM_NOT_FOUND` indicates that a stream was not + * found. + */ +#define NGTCP2_ERR_STREAM_NOT_FOUND -222 +/** + * @macro + * + * :macro:`NGTCP2_ERR_STREAM_STATE` indicates that a requested + * operation is not allowed at the current stream state. + */ +#define NGTCP2_ERR_STREAM_STATE -226 +/** + * @macro + * + * :macro:`NGTCP2_ERR_RECV_VERSION_NEGOTIATION` indicates that Version + * Negotiation packet was received. + */ +#define NGTCP2_ERR_RECV_VERSION_NEGOTIATION -229 +/** + * @macro + * + * :macro:`NGTCP2_ERR_CLOSING` indicates that connection is in closing + * state. + */ +#define NGTCP2_ERR_CLOSING -230 +/** + * @macro + * + * :macro:`NGTCP2_ERR_DRAINING` indicates that connection is in + * draining state. + */ +#define NGTCP2_ERR_DRAINING -231 +/** + * @macro + * + * :macro:`NGTCP2_ERR_TRANSPORT_PARAM` indicates a general transport + * parameter error. + */ +#define NGTCP2_ERR_TRANSPORT_PARAM -234 +/** + * @macro + * + * :macro:`NGTCP2_ERR_DISCARD_PKT` indicates a packet was discarded. + */ +#define NGTCP2_ERR_DISCARD_PKT -235 +/** + * @macro + * + * :macro:`NGTCP2_ERR_CONN_ID_BLOCKED` indicates that there is no + * spare Connection ID available. + */ +#define NGTCP2_ERR_CONN_ID_BLOCKED -237 +/** + * @macro + * + * :macro:`NGTCP2_ERR_INTERNAL` indicates an internal error. + */ +#define NGTCP2_ERR_INTERNAL -238 +/** + * @macro + * + * :macro:`NGTCP2_ERR_CRYPTO_BUFFER_EXCEEDED` indicates that a crypto + * buffer exceeded. + */ +#define NGTCP2_ERR_CRYPTO_BUFFER_EXCEEDED -239 +/** + * @macro + * + * :macro:`NGTCP2_ERR_WRITE_MORE` indicates + * :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE` is used and a function call + * succeeded. + */ +#define NGTCP2_ERR_WRITE_MORE -240 +/** + * @macro + * + * :macro:`NGTCP2_ERR_RETRY` indicates that server should send Retry + * packet. + */ +#define NGTCP2_ERR_RETRY -241 +/** + * @macro + * + * :macro:`NGTCP2_ERR_DROP_CONN` indicates that an endpoint should + * drop connection immediately. + */ +#define NGTCP2_ERR_DROP_CONN -242 +/** + * @macro + * + * :macro:`NGTCP2_ERR_AEAD_LIMIT_REACHED` indicates AEAD encryption + * limit is reached and key update is not available. An endpoint + * should drop connection immediately. + */ +#define NGTCP2_ERR_AEAD_LIMIT_REACHED -243 +/** + * @macro + * + * :macro:`NGTCP2_ERR_NO_VIABLE_PATH` indicates that path validation + * could not probe that a path is capable of sending UDP datagram + * payload of size at least 1200 bytes. + */ +#define NGTCP2_ERR_NO_VIABLE_PATH -244 +/** + * @macro + * + * :macro:`NGTCP2_ERR_VERSION_NEGOTIATION` indicates that server + * should send Version Negotiation packet. + */ +#define NGTCP2_ERR_VERSION_NEGOTIATION -245 +/** + * @macro + * + * :macro:`NGTCP2_ERR_HANDSHAKE_TIMEOUT` indicates that QUIC + * connection is not established before the specified deadline. + */ +#define NGTCP2_ERR_HANDSHAKE_TIMEOUT -246 +/** + * @macro + * + * :macro:`NGTCP2_ERR_VERSION_NEGOTIATION_FAILURE` indicates the + * version negotiation failed. + */ +#define NGTCP2_ERR_VERSION_NEGOTIATION_FAILURE -247 +/** + * @macro + * + * :macro:`NGTCP2_ERR_IDLE_CLOSE` indicates the connection should be + * closed silently because of idle timeout. + */ +#define NGTCP2_ERR_IDLE_CLOSE -248 +/** + * @macro + * + * :macro:`NGTCP2_ERR_FATAL` indicates that error codes less than this + * value is fatal error. When this error is returned, an endpoint + * should drop connection immediately. + */ +#define NGTCP2_ERR_FATAL -500 +/** + * @macro + * + * :macro:`NGTCP2_ERR_NOMEM` indicates out of memory. + */ +#define NGTCP2_ERR_NOMEM -501 +/** + * @macro + * + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` indicates that user defined + * callback function failed. + */ +#define NGTCP2_ERR_CALLBACK_FAILURE -502 + +/** + * @macrosection + * + * QUIC packet header flags + */ + +/** + * @macro + * + * :macro:`NGTCP2_PKT_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_PKT_FLAG_NONE 0x00u + +/** + * @macro + * + * :macro:`NGTCP2_PKT_FLAG_LONG_FORM` indicates the Long header packet + * header. + */ +#define NGTCP2_PKT_FLAG_LONG_FORM 0x01u + +/** + * @macro + * + * :macro:`NGTCP2_PKT_FLAG_FIXED_BIT_CLEAR` indicates that Fixed Bit + * (aka QUIC bit) is not set. + */ +#define NGTCP2_PKT_FLAG_FIXED_BIT_CLEAR 0x02u + +/** + * @macro + * + * :macro:`NGTCP2_PKT_FLAG_KEY_PHASE` indicates Key Phase bit set. + */ +#define NGTCP2_PKT_FLAG_KEY_PHASE 0x04u + +/** + * @enum + * + * :type:`ngtcp2_pkt_type` defines QUIC version-independent QUIC + * packet types. + */ +typedef enum ngtcp2_pkt_type { + /** + * :enum:`NGTCP2_PKT_VERSION_NEGOTIATION` is defined by libngtcp2 + * for convenience. + */ + NGTCP2_PKT_VERSION_NEGOTIATION = 0x80, + /** + * :enum:`NGTCP2_PKT_STATELESS_RESET` is defined by libngtcp2 for + * convenience. + */ + NGTCP2_PKT_STATELESS_RESET = 0x81, + /** + * :enum:`NGTCP2_PKT_INITIAL` indicates Initial packet. + */ + NGTCP2_PKT_INITIAL = 0x10, + /** + * :enum:`NGTCP2_PKT_0RTT` indicates 0RTT packet. + */ + NGTCP2_PKT_0RTT = 0x11, + /** + * :enum:`NGTCP2_PKT_HANDSHAKE` indicates Handshake packet. + */ + NGTCP2_PKT_HANDSHAKE = 0x12, + /** + * :enum:`NGTCP2_PKT_RETRY` indicates Retry packet. + */ + NGTCP2_PKT_RETRY = 0x13, + /** + * :enum:`NGTCP2_PKT_1RTT` is defined by libngtcp2 for convenience. + */ + NGTCP2_PKT_1RTT = 0x40 +} ngtcp2_pkt_type; + +/** + * @macrosection + * + * QUIC transport error code + */ + +/** + * @macro + * + * :macro:`NGTCP2_NO_ERROR` is QUIC transport error code ``NO_ERROR``. + */ +#define NGTCP2_NO_ERROR 0x0u + +/** + * @macro + * + * :macro:`NGTCP2_INTERNAL_ERROR` is QUIC transport error code + * ``INTERNAL_ERROR``. + */ +#define NGTCP2_INTERNAL_ERROR 0x1u + +/** + * @macro + * + * :macro:`NGTCP2_CONNECTION_REFUSED` is QUIC transport error code + * ``CONNECTION_REFUSED``. + */ +#define NGTCP2_CONNECTION_REFUSED 0x2u + +/** + * @macro + * + * :macro:`NGTCP2_FLOW_CONTROL_ERROR` is QUIC transport error code + * ``FLOW_CONTROL_ERROR``. + */ +#define NGTCP2_FLOW_CONTROL_ERROR 0x3u + +/** + * @macro + * + * :macro:`NGTCP2_STREAM_LIMIT_ERROR` is QUIC transport error code + * ``STREAM_LIMIT_ERROR``. + */ +#define NGTCP2_STREAM_LIMIT_ERROR 0x4u + +/** + * @macro + * + * :macro:`NGTCP2_STREAM_STATE_ERROR` is QUIC transport error code + * ``STREAM_STATE_ERROR``. + */ +#define NGTCP2_STREAM_STATE_ERROR 0x5u + +/** + * @macro + * + * :macro:`NGTCP2_FINAL_SIZE_ERROR` is QUIC transport error code + * ``FINAL_SIZE_ERROR``. + */ +#define NGTCP2_FINAL_SIZE_ERROR 0x6u + +/** + * @macro + * + * :macro:`NGTCP2_FRAME_ENCODING_ERROR` is QUIC transport error code + * ``FRAME_ENCODING_ERROR``. + */ +#define NGTCP2_FRAME_ENCODING_ERROR 0x7u + +/** + * @macro + * + * :macro:`NGTCP2_TRANSPORT_PARAMETER_ERROR` is QUIC transport error + * code ``TRANSPORT_PARAMETER_ERROR``. + */ +#define NGTCP2_TRANSPORT_PARAMETER_ERROR 0x8u + +/** + * @macro + * + * :macro:`NGTCP2_CONNECTION_ID_LIMIT_ERROR` is QUIC transport error + * code ``CONNECTION_ID_LIMIT_ERROR``. + */ +#define NGTCP2_CONNECTION_ID_LIMIT_ERROR 0x9u + +/** + * @macro + * + * :macro:`NGTCP2_PROTOCOL_VIOLATION` is QUIC transport error code + * ``PROTOCOL_VIOLATION``. + */ +#define NGTCP2_PROTOCOL_VIOLATION 0xau + +/** + * @macro + * + * :macro:`NGTCP2_INVALID_TOKEN` is QUIC transport error code + * ``INVALID_TOKEN``. + */ +#define NGTCP2_INVALID_TOKEN 0xbu + +/** + * @macro + * + * :macro:`NGTCP2_APPLICATION_ERROR` is QUIC transport error code + * ``APPLICATION_ERROR``. + */ +#define NGTCP2_APPLICATION_ERROR 0xcu + +/** + * @macro + * + * :macro:`NGTCP2_CRYPTO_BUFFER_EXCEEDED` is QUIC transport error code + * ``CRYPTO_BUFFER_EXCEEDED``. + */ +#define NGTCP2_CRYPTO_BUFFER_EXCEEDED 0xdu + +/** + * @macro + * + * :macro:`NGTCP2_KEY_UPDATE_ERROR` is QUIC transport error code + * ``KEY_UPDATE_ERROR``. + */ +#define NGTCP2_KEY_UPDATE_ERROR 0xeu + +/** + * @macro + * + * :macro:`NGTCP2_AEAD_LIMIT_REACHED` is QUIC transport error code + * ``AEAD_LIMIT_REACHED``. + */ +#define NGTCP2_AEAD_LIMIT_REACHED 0xfu + +/** + * @macro + * + * :macro:`NGTCP2_NO_VIABLE_PATH` is QUIC transport error code + * ``NO_VIABLE_PATH``. + */ +#define NGTCP2_NO_VIABLE_PATH 0x10u + +/** + * @macro + * + * :macro:`NGTCP2_CRYPTO_ERROR` is QUIC transport error code + * ``CRYPTO_ERROR``. + */ +#define NGTCP2_CRYPTO_ERROR 0x100u + +/** + * @macro + * + * :macro:`NGTCP2_VERSION_NEGOTIATION_ERROR` is QUIC transport error + * code ``VERSION_NEGOTIATION_ERROR``. + * + * https://datatracker.ietf.org/doc/html/draft-ietf-quic-version-negotiation-14 + */ +#define NGTCP2_VERSION_NEGOTIATION_ERROR 0x11 + +/** + * @enum + * + * :type:`ngtcp2_path_validation_result` defines path validation + * result code. + */ +typedef enum ngtcp2_path_validation_result { + /** + * :enum:`NGTCP2_PATH_VALIDATION_RESULT_SUCCESS` indicates + * successful validation. + */ + NGTCP2_PATH_VALIDATION_RESULT_SUCCESS, + /** + * :enum:`NGTCP2_PATH_VALIDATION_RESULT_FAILURE` indicates + * validation failure. + */ + NGTCP2_PATH_VALIDATION_RESULT_FAILURE, + /** + * :enum:`NGTCP2_PATH_VALIDATION_RESULT_ABORTED` indicates that path + * validation was aborted. + */ + NGTCP2_PATH_VALIDATION_RESULT_ABORTED +} ngtcp2_path_validation_result; + +/** + * @typedef + * + * :type:`ngtcp2_tstamp` is a timestamp with nanosecond resolution. + * ``UINT64_MAX`` is an invalid value. + */ +typedef uint64_t ngtcp2_tstamp; + +/** + * @typedef + * + * :type:`ngtcp2_duration` is a period of time in nanosecond + * resolution. ``UINT64_MAX`` is an invalid value. + */ +typedef uint64_t ngtcp2_duration; + +/** + * @struct + * + * :type:`ngtcp2_cid` holds a Connection ID. + */ +typedef struct ngtcp2_cid { + /** + * :member:`datalen` is the length of Connection ID. + */ + size_t datalen; + /** + * :member:`data` is the buffer to store Connection ID. + */ + uint8_t data[NGTCP2_MAX_CIDLEN]; +} ngtcp2_cid; + +/** + * @struct + * + * :type:`ngtcp2_vec` is struct iovec compatible structure to + * reference arbitrary array of bytes. + */ +typedef struct ngtcp2_vec { + /** + * :member:`base` points to the data. + */ + uint8_t *base; + /** + * :member:`len` is the number of bytes which the buffer pointed by + * base contains. + */ + size_t len; +} ngtcp2_vec; + +/** + * @function + * + * `ngtcp2_cid_init` initializes Connection ID |cid| with the byte + * string pointed by |data| and its length is |datalen|. |datalen| + * must be at most :macro:`NGTCP2_MAX_CIDLEN`. + */ +NGTCP2_EXTERN void ngtcp2_cid_init(ngtcp2_cid *cid, const uint8_t *data, + size_t datalen); + +/** + * @function + * + * `ngtcp2_cid_eq` returns nonzero if |a| and |b| share the same + * Connection ID. + */ +NGTCP2_EXTERN int ngtcp2_cid_eq(const ngtcp2_cid *a, const ngtcp2_cid *b); + +/** + * @struct + * + * :type:`ngtcp2_pkt_hd` represents QUIC packet header. + */ +typedef struct ngtcp2_pkt_hd { + /** + * :member:`dcid` is Destination Connection ID. + */ + ngtcp2_cid dcid; + /** + * :member:`scid` is Source Connection ID. + */ + ngtcp2_cid scid; + /** + * :member:`pkt_num` is a packet number. + */ + int64_t pkt_num; + /** + * :member:`token` contains token for Initial + * packet. + */ + const uint8_t *token; + /** + * :member:`tokenlen` is the length of :member:`token`. + */ + size_t tokenlen; + /** + * :member:`pkt_numlen` is the number of bytes spent to encode + * :member:`pkt_num`. + */ + size_t pkt_numlen; + /** + * :member:`len` is the sum of :member:`pkt_numlen` and the length + * of QUIC packet payload. + */ + size_t len; + /** + * :member:`version` is QUIC version. + */ + uint32_t version; + /** + * :member:`type` is a type of QUIC packet. See + * :type:`ngtcp2_pkt_type`. + */ + uint8_t type; + /** + * :member:`flags` is zero or more of :macro:`NGTCP2_PKT_FLAG_* + * <NGTCP2_PKT_FLAG_NONE>`. + */ + uint8_t flags; +} ngtcp2_pkt_hd; + +/** + * @struct + * + * :type:`ngtcp2_pkt_stateless_reset` represents Stateless Reset. + */ +typedef struct ngtcp2_pkt_stateless_reset { + /** + * :member:`stateless_reset_token` contains stateless reset token. + */ + uint8_t stateless_reset_token[NGTCP2_STATELESS_RESET_TOKENLEN]; + /** + * :member:`rand` points a buffer which contains random bytes + * section. + */ + const uint8_t *rand; + /** + * :member:`randlen` is the number of random bytes. + */ + size_t randlen; +} ngtcp2_pkt_stateless_reset; + +/** + * @enum + * + * :type:`ngtcp2_transport_params_type` defines TLS message type which + * carries transport parameters. + */ +typedef enum ngtcp2_transport_params_type { + /** + * :enum:`NGTCP2_TRANSPORT_PARAMS_TYPE_CLIENT_HELLO` is Client Hello + * TLS message. + */ + NGTCP2_TRANSPORT_PARAMS_TYPE_CLIENT_HELLO, + /** + * :enum:`NGTCP2_TRANSPORT_PARAMS_TYPE_ENCRYPTED_EXTENSIONS` is + * Encrypted Extensions TLS message. + */ + NGTCP2_TRANSPORT_PARAMS_TYPE_ENCRYPTED_EXTENSIONS +} ngtcp2_transport_params_type; + +/** + * @macrosection + * + * QUIC transport parameters related macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_DEFAULT_MAX_RECV_UDP_PAYLOAD_SIZE` is the default + * value of max_udp_payload_size transport parameter. + */ +#define NGTCP2_DEFAULT_MAX_RECV_UDP_PAYLOAD_SIZE 65527 + +/** + * @macro + * + * :macro:`NGTCP2_DEFAULT_ACK_DELAY_EXPONENT` is a default value of + * scaling factor of ACK Delay field in ACK frame. + */ +#define NGTCP2_DEFAULT_ACK_DELAY_EXPONENT 3 + +/** + * @macro + * + * :macro:`NGTCP2_DEFAULT_MAX_ACK_DELAY` is a default value of the + * maximum amount of time in nanoseconds by which endpoint delays + * sending acknowledgement. + */ +#define NGTCP2_DEFAULT_MAX_ACK_DELAY (25 * NGTCP2_MILLISECONDS) + +/** + * @macro + * + * :macro:`NGTCP2_DEFAULT_ACTIVE_CONNECTION_ID_LIMIT` is the default + * value of active_connection_id_limit transport parameter value if + * omitted. + */ +#define NGTCP2_DEFAULT_ACTIVE_CONNECTION_ID_LIMIT 2 + +/** + * @macro + * + * :macro:`NGTCP2_TLSEXT_QUIC_TRANSPORT_PARAMETERS_V1` is TLS + * extension type of quic_transport_parameters. + */ +#define NGTCP2_TLSEXT_QUIC_TRANSPORT_PARAMETERS_V1 0x39u + +/** + * @macro + * + * :macro:`NGTCP2_TLSEXT_QUIC_TRANSPORT_PARAMETERS_DRAFT` is TLS + * extension type of quic_transport_parameters used during draft + * development. + */ +#define NGTCP2_TLSEXT_QUIC_TRANSPORT_PARAMETERS_DRAFT 0xffa5u + +#ifdef NGTCP2_USE_GENERIC_SOCKADDR +typedef struct ngtcp2_sockaddr { + uint16_t sa_family; + uint8_t sa_data[14]; +} ngtcp2_sockaddr; + +typedef struct ngtcp2_in_addr { + uint32_t s_addr; +} ngtcp2_in_addr; + +typedef struct ngtcp2_sockaddr_in { + uint16_t sin_family; + uint16_t sin_port; + ngtcp2_in_addr sin_addr; + uint8_t sin_zero[8]; +} ngtcp2_sockaddr_in; + +# define NGTCP2_SS_MAXSIZE 128 +# define NGTCP2_SS_ALIGNSIZE (sizeof(uint64_t)) +# define NGTCP2_SS_PAD1SIZE (NGTCP2_SS_ALIGNSIZE - sizeof(uint16_t)) +# define NGTCP2_SS_PAD2SIZE \ + (NGTCP2_SS_MAXSIZE - \ + (sizeof(uint16_t) + NGTCP2_SS_PAD1SIZE + NGTCP2_SS_ALIGNSIZE)) + +typedef struct ngtcp2_sockaddr_storage { + uint16_t ss_family; + uint8_t _ss_pad1[NGTCP2_SS_PAD1SIZE]; + uint64_t _ss_align; + uint8_t _ss_pad2[NGTCP2_SS_PAD2SIZE]; +} ngtcp2_sockaddr_storage; + +# undef NGTCP2_SS_PAD2SIZE +# undef NGTCP2_SS_PAD1SIZE +# undef NGTCP2_SS_ALIGNSIZE +# undef NGTCP2_SS_MAXSIZE + +typedef uint32_t ngtcp2_socklen; +#else +/** + * @typedef + * + * :type:`ngtcp2_sockaddr` is typedefed to struct sockaddr. If + * :macro:`NGTCP2_USE_GENERIC_SOCKADDR` is defined, it is typedefed to + * the generic struct sockaddr defined in ngtcp2.h. + */ +typedef struct sockaddr ngtcp2_sockaddr; +/** + * @typedef + * + * :type:`ngtcp2_sockaddr_storage` is typedefed to struct + * sockaddr_storage. If :macro:`NGTCP2_USE_GENERIC_SOCKADDR` is + * defined, it is typedefed to the generic struct sockaddr_storage + * defined in ngtcp2.h. + */ +typedef struct sockaddr_storage ngtcp2_sockaddr_storage; +/** + * @typedef + * + * :type:`ngtcp2_sockaddr_in` is typedefed to struct sockaddr_in. If + * :macro:`NGTCP2_USE_GENERIC_SOCKADDR` is defined, it is typedefed to + * the generic struct sockaddr_in defined in ngtcp2.h. + */ +typedef struct sockaddr_in ngtcp2_sockaddr_in; +/** + * @typedef + * + * :type:`ngtcp2_socklen` is typedefed to socklen_t. If + * :macro:`NGTCP2_USE_GENERIC_SOCKADDR` is defined, it is typedefed to + * uint32_t. + */ +typedef socklen_t ngtcp2_socklen; +#endif + +#if defined(NGTCP2_USE_GENERIC_SOCKADDR) || \ + defined(NGTCP2_USE_GENERIC_IPV6_SOCKADDR) +typedef struct ngtcp2_in6_addr { + uint8_t in6_addr[16]; +} ngtcp2_in6_addr; + +typedef struct ngtcp2_sockaddr_in6 { + uint16_t sin6_family; + uint16_t sin6_port; + uint32_t sin6_flowinfo; + ngtcp2_in6_addr sin6_addr; + uint32_t sin6_scope_id; +} ngtcp2_sockaddr_in6; +#else +/** + * @typedef + * + * :type:`ngtcp2_sockaddr_in6` is typedefed to struct sockaddr_in6. + * If :macro:`NGTCP2_USE_GENERIC_SOCKADDR` is defined, it is typedefed + * to the generic struct sockaddr_in6 defined in ngtcp2.h. + */ +typedef struct sockaddr_in6 ngtcp2_sockaddr_in6; +#endif + +/** + * @struct + * + * :type:`ngtcp2_sockaddr_union` conveniently includes all supported + * address types. + */ +typedef union ngtcp2_sockaddr_union { + ngtcp2_sockaddr sa; + ngtcp2_sockaddr_in in; + ngtcp2_sockaddr_in6 in6; +} ngtcp2_sockaddr_union; + +/** + * @struct + * + * :type:`ngtcp2_preferred_addr` represents preferred address + * structure. + */ +typedef struct ngtcp2_preferred_addr { + /** + * :member:`cid` is a Connection ID. + */ + ngtcp2_cid cid; + /** + * :member:`ipv4` contains IPv4 address and port. + */ + ngtcp2_sockaddr_in ipv4; + /** + * :member:`ipv6` contains IPv4 address and port. + */ + ngtcp2_sockaddr_in6 ipv6; + /** + * :member:`ipv4_present` indicates that :member:`ipv4` contains + * IPv4 address and port. + */ + uint8_t ipv4_present; + /** + * :member:`ipv6_present` indicates that :member:`ipv6` contains + * IPv6 address and port. + */ + uint8_t ipv6_present; + /** + * :member:`stateless_reset_token` contains stateless reset token. + */ + uint8_t stateless_reset_token[NGTCP2_STATELESS_RESET_TOKENLEN]; +} ngtcp2_preferred_addr; + +/** + * @struct + * + * :type:`ngtcp2_version_info` represents version_information + * structure. + */ +typedef struct ngtcp2_version_info { + /** + * :member:`chosen_version` is the version chosen by the sender. + */ + uint32_t chosen_version; + /** + * :member:`available_versions` points the wire image of + * available_versions field. The each version is therefore in + * network byte order. + */ + const uint8_t *available_versions; + /** + * :member:`available_versionslen` is the number of bytes pointed by + * :member:`available_versions`, not the number of versions + * included. + */ + size_t available_versionslen; +} ngtcp2_version_info; + +#define NGTCP2_TRANSPORT_PARAMS_VERSION_V1 1 +#define NGTCP2_TRANSPORT_PARAMS_VERSION NGTCP2_TRANSPORT_PARAMS_VERSION_V1 + +/** + * @struct + * + * :type:`ngtcp2_transport_params` represents QUIC transport + * parameters. + */ +typedef struct ngtcp2_transport_params { + /** + * :member:`preferred_address` contains preferred address if + * :member:`preferred_address_present` is nonzero. + */ + ngtcp2_preferred_addr preferred_address; + /** + * :member:`original_dcid` is the Destination Connection ID field + * from the first Initial packet from client. Server must specify + * this field. It is expected that application knows the original + * Destination Connection ID even if it sends Retry packet, for + * example, by including it in retry token. Otherwise, application + * should not specify this field. + */ + ngtcp2_cid original_dcid; + /** + * :member:`initial_scid` is the Source Connection ID field from the + * first Initial packet the endpoint sends. Application should not + * specify this field. + */ + ngtcp2_cid initial_scid; + /** + * :member:`retry_scid` is the Source Connection ID field from Retry + * packet. Only server uses this field. If server application + * received Initial packet with retry token from client and server + * verified its token, server application must set Destination + * Connection ID field from the Initial packet to this field and set + * :member:`retry_scid_present` to nonzero. Server application must + * verify that the Destination Connection ID from Initial packet was + * sent in Retry packet by, for example, including the Connection ID + * in a token, or including it in AAD when encrypting a token. + */ + ngtcp2_cid retry_scid; + /** + * :member:`initial_max_stream_data_bidi_local` is the size of flow + * control window of locally initiated stream. This is the number + * of bytes that the remote endpoint can send and the local endpoint + * must ensure that it has enough buffer to receive them. + */ + uint64_t initial_max_stream_data_bidi_local; + /** + * :member:`initial_max_stream_data_bidi_remote` is the size of flow + * control window of remotely initiated stream. This is the number + * of bytes that the remote endpoint can send and the local endpoint + * must ensure that it has enough buffer to receive them. + */ + uint64_t initial_max_stream_data_bidi_remote; + /** + * :member:`initial_max_stream_data_uni` is the size of flow control + * window of remotely initiated unidirectional stream. This is the + * number of bytes that the remote endpoint can send and the local + * endpoint must ensure that it has enough buffer to receive them. + */ + uint64_t initial_max_stream_data_uni; + /** + * :member:`initial_max_data` is the connection level flow control + * window. + */ + uint64_t initial_max_data; + /** + * :member:`initial_max_streams_bidi` is the number of concurrent + * streams that the remote endpoint can create. + */ + uint64_t initial_max_streams_bidi; + /** + * :member:`initial_max_streams_uni` is the number of concurrent + * unidirectional streams that the remote endpoint can create. + */ + uint64_t initial_max_streams_uni; + /** + * :member:`max_idle_timeout` is a duration during which sender + * allows quiescent. + */ + ngtcp2_duration max_idle_timeout; + /** + * :member:`max_udp_payload_size` is the maximum datagram size that + * the endpoint can receive. + */ + uint64_t max_udp_payload_size; + /** + * :member:`active_connection_id_limit` is the maximum number of + * Connection ID that sender can store. + */ + uint64_t active_connection_id_limit; + /** + * :member:`ack_delay_exponent` is the exponent used in ACK Delay + * field in ACK frame. + */ + uint64_t ack_delay_exponent; + /** + * :member:`max_ack_delay` is the maximum acknowledgement delay by + * which the endpoint will delay sending acknowledgements. + */ + ngtcp2_duration max_ack_delay; + /** + * :member:`max_datagram_frame_size` is the maximum size of DATAGRAM + * frame that this endpoint willingly receives. Specifying 0 + * disables DATAGRAM support. See + * https://datatracker.ietf.org/doc/html/rfc9221 + */ + uint64_t max_datagram_frame_size; + /** + * :member:`stateless_reset_token_present` is nonzero if + * :member:`stateless_reset_token` field is set. + */ + uint8_t stateless_reset_token_present; + /** + * :member:`disable_active_migration` is nonzero if the endpoint + * does not support active connection migration. + */ + uint8_t disable_active_migration; + /** + * :member:`retry_scid_present` is nonzero if :member:`retry_scid` + * field is set. + */ + uint8_t retry_scid_present; + /** + * :member:`preferred_address_present` is nonzero if + * :member:`preferred_address` is set. + */ + uint8_t preferred_address_present; + /** + * :member:`stateless_reset_token` contains stateless reset token. + */ + uint8_t stateless_reset_token[NGTCP2_STATELESS_RESET_TOKENLEN]; + /** + * :member:`grease_quic_bit` is nonzero if sender supports "Greasing + * the QUIC Bit" extension. See :rfc:`9287`. Note that the local + * endpoint always enables greasing QUIC bit regardless of this + * field value. + */ + uint8_t grease_quic_bit; + /** + * :member:`version_info` contains version_information field if + * :member:`version_info_present` is nonzero. Application should + * not specify this field. + */ + ngtcp2_version_info version_info; + /** + * :member:`version_info_present` is nonzero if + * :member:`version_info` is set. Application should not specify + * this field. + */ + uint8_t version_info_present; +} ngtcp2_transport_params; + +/** + * @enum + * + * :type:`ngtcp2_pktns_id` defines packet number space identifier. + */ +typedef enum ngtcp2_pktns_id { + /** + * :enum:`NGTCP2_PKTNS_ID_INITIAL` is the Initial packet number + * space. + */ + NGTCP2_PKTNS_ID_INITIAL, + /** + * :enum:`NGTCP2_PKTNS_ID_HANDSHAKE` is the Handshake packet number + * space. + */ + NGTCP2_PKTNS_ID_HANDSHAKE, + /** + * :enum:`NGTCP2_PKTNS_ID_APPLICATION` is the Application data + * packet number space. + */ + NGTCP2_PKTNS_ID_APPLICATION, + /** + * :enum:`NGTCP2_PKTNS_ID_MAX` is defined to get the number of + * packet number spaces. + */ + NGTCP2_PKTNS_ID_MAX +} ngtcp2_pktns_id; + +#define NGTCP2_CONN_STAT_VERSION_V1 1 +#define NGTCP2_CONN_STAT_VERSION NGTCP2_CONN_STAT_VERSION_V1 + +/** + * @struct + * + * :type:`ngtcp2_conn_stat` holds various connection statistics, and + * computed data for recovery and congestion controller. + */ +typedef struct ngtcp2_conn_stat { + /** + * :member:`latest_rtt` is the latest RTT sample which is not + * adjusted by acknowledgement delay. + */ + ngtcp2_duration latest_rtt; + /** + * :member:`min_rtt` is the minimum RTT seen so far. It is not + * adjusted by acknowledgement delay. + */ + ngtcp2_duration min_rtt; + /** + * :member:`smoothed_rtt` is the smoothed RTT. + */ + ngtcp2_duration smoothed_rtt; + /** + * :member:`rttvar` is a mean deviation of observed RTT. + */ + ngtcp2_duration rttvar; + /** + * :member:`initial_rtt` is the initial RTT which is used when no + * RTT sample is available. + */ + ngtcp2_duration initial_rtt; + /** + * :member:`first_rtt_sample_ts` is the timestamp when the first RTT + * sample is obtained. + */ + ngtcp2_tstamp first_rtt_sample_ts; + /** + * :member:`pto_count` is the count of successive PTO timer + * expiration. + */ + size_t pto_count; + /** + * :member:`loss_detection_timer` is the deadline of the current + * loss detection timer. + */ + ngtcp2_tstamp loss_detection_timer; + /** + * :member:`last_tx_pkt_ts` corresponds to + * time_of_last_ack_eliciting_packet in :rfc:`9002`. + */ + ngtcp2_tstamp last_tx_pkt_ts[NGTCP2_PKTNS_ID_MAX]; + /** + * :member:`loss_time` corresponds to loss_time in :rfc:`9002`. + */ + ngtcp2_tstamp loss_time[NGTCP2_PKTNS_ID_MAX]; + /** + * :member:`cwnd` is the size of congestion window. + */ + uint64_t cwnd; + /** + * :member:`ssthresh` is slow start threshold. + */ + uint64_t ssthresh; + /** + * :member:`congestion_recovery_start_ts` is the timestamp when + * congestion recovery started. + */ + ngtcp2_tstamp congestion_recovery_start_ts; + /** + * :member:`bytes_in_flight` is the number in bytes of all sent + * packets which have not been acknowledged. + */ + uint64_t bytes_in_flight; + /** + * :member:`max_tx_udp_payload_size` is the maximum size of UDP + * datagram payload that this endpoint transmits. It is used by + * congestion controller to compute congestion window. + */ + size_t max_tx_udp_payload_size; + /** + * :member:`delivery_rate_sec` is the current sending rate measured + * in byte per second. + */ + uint64_t delivery_rate_sec; + /** + * :member:`pacing_rate` is the current packet sending rate computed + * by a congestion controller. 0 if a congestion controller does + * not set pacing rate. Even if this value is set to 0, the library + * paces packets. + */ + double pacing_rate; + /** + * :member:`send_quantum` is the maximum size of a data aggregate + * scheduled and transmitted together. + */ + size_t send_quantum; +} ngtcp2_conn_stat; + +/** + * @enum + * + * :type:`ngtcp2_cc_algo` defines congestion control algorithms. + */ +typedef enum ngtcp2_cc_algo { + /** + * :enum:`NGTCP2_CC_ALGO_RENO` represents Reno. + */ + NGTCP2_CC_ALGO_RENO = 0x00, + /** + * :enum:`NGTCP2_CC_ALGO_CUBIC` represents Cubic. + */ + NGTCP2_CC_ALGO_CUBIC = 0x01, + /** + * :enum:`NGTCP2_CC_ALGO_BBR` represents BBR. + */ + NGTCP2_CC_ALGO_BBR = 0x02, + /** + * :enum:`NGTCP2_CC_ALGO_BBR2` represents BBR v2. + */ + NGTCP2_CC_ALGO_BBR2 = 0x03 +} ngtcp2_cc_algo; + +/** + * @functypedef + * + * :type:`ngtcp2_printf` is a callback function for logging. + * |user_data| is the same object passed to `ngtcp2_conn_client_new` + * or `ngtcp2_conn_server_new`. + */ +typedef void (*ngtcp2_printf)(void *user_data, const char *format, ...); + +/** + * @macrosection + * + * QLog related macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_QLOG_WRITE_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_QLOG_WRITE_FLAG_NONE 0x00u +/** + * @macro + * + * :macro:`NGTCP2_QLOG_WRITE_FLAG_FIN` indicates that this is the + * final call to :type:`ngtcp2_qlog_write` in the current connection. + */ +#define NGTCP2_QLOG_WRITE_FLAG_FIN 0x01u + +/** + * @struct + * + * :type:`ngtcp2_rand_ctx` is a wrapper around native random number + * generator. It is opaque to the ngtcp2 library. This might be + * useful if application needs to specify random number generator per + * thread or per connection. + */ +typedef struct ngtcp2_rand_ctx { + /** + * :member:`native_handle` is a pointer to an underlying random + * number generator. + */ + void *native_handle; +} ngtcp2_rand_ctx; + +/** + * @functypedef + * + * :type:`ngtcp2_qlog_write` is a callback function which is called to + * write qlog |data| of length |datalen| bytes. |flags| is bitwise OR + * of zero or more of :macro:`NGTCP2_QLOG_WRITE_FLAG_* + * <NGTCP2_QLOG_WRITE_FLAG_NONE>`. If + * :macro:`NGTCP2_QLOG_WRITE_FLAG_FIN` is set, |datalen| may be 0. + */ +typedef void (*ngtcp2_qlog_write)(void *user_data, uint32_t flags, + const void *data, size_t datalen); + +/** + * @struct + * + * :type:`ngtcp2_qlog_settings` is a set of settings for qlog. + */ +typedef struct ngtcp2_qlog_settings { + /** + * :member:`odcid` is Original Destination Connection ID sent by + * client. It is used as group_id and ODCID fields. Client ignores + * this field and uses dcid parameter passed to + * `ngtcp2_conn_client_new()`. + */ + ngtcp2_cid odcid; + /** + * :member:`write` is a callback function to write qlog. Setting + * ``NULL`` disables qlog. + */ + ngtcp2_qlog_write write; +} ngtcp2_qlog_settings; + +#define NGTCP2_SETTINGS_VERSION_V1 1 +#define NGTCP2_SETTINGS_VERSION NGTCP2_SETTINGS_VERSION_V1 + +/** + * @struct + * + * :type:`ngtcp2_settings` defines QUIC connection settings. + */ +typedef struct ngtcp2_settings { + /** + * :member:`qlog` is qlog settings. + */ + ngtcp2_qlog_settings qlog; + /** + * :member:`cc_algo` specifies congestion control algorithm. + */ + ngtcp2_cc_algo cc_algo; + /** + * :member:`initial_ts` is an initial timestamp given to the + * library. + */ + ngtcp2_tstamp initial_ts; + /** + * :member:`initial_rtt` is an initial RTT. + */ + ngtcp2_duration initial_rtt; + /** + * :member:`log_printf` is a function that the library uses to write + * logs. ``NULL`` means no logging output. It is nothing to do + * with qlog. + */ + ngtcp2_printf log_printf; + /** + * :member:`max_tx_udp_payload_size` is the maximum size of UDP + * datagram payload that this endpoint transmits. It is used by + * congestion controller to compute congestion window. + */ + size_t max_tx_udp_payload_size; + /** + * :member:`token` is a token from Retry packet or NEW_TOKEN frame. + * + * Server sets this field if it received the token in Client Initial + * packet and successfully validated. + * + * Client sets this field if it intends to send token in its Initial + * packet. + * + * `ngtcp2_conn_server_new` and `ngtcp2_conn_client_new` make a copy + * of token. + */ + const uint8_t *token; + /** + * :member:`tokenlen` is the length of :member:`token`. + */ + size_t tokenlen; + /** + * :member:`rand_ctx` is an optional random number generator to be + * passed to :type:`ngtcp2_rand` callback. + */ + ngtcp2_rand_ctx rand_ctx; + /** + * :member:`max_window` is the maximum connection-level flow control + * window if connection-level window auto-tuning is enabled. The + * connection-level window auto tuning is enabled if nonzero value + * is specified in this field. The initial value of window size is + * :member:`ngtcp2_transport_params.initial_max_data`. The window + * size is scaled up to the value specified in this field. + */ + uint64_t max_window; + /** + * :member:`max_stream_window` is the maximum stream-level flow + * control window if stream-level window auto-tuning is enabled. + * The stream-level window auto-tuning is enabled if nonzero value + * is specified in this field. The initial value of window size is + * :member:`ngtcp2_transport_params.initial_max_stream_data_bidi_remote`, + * :member:`ngtcp2_transport_params.initial_max_stream_data_bidi_local`, + * or :member:`ngtcp2_transport_params.initial_max_stream_data_uni`, + * depending on the type of stream. The window size is scaled up to + * the value specified in this field. + */ + uint64_t max_stream_window; + /** + * :member:`ack_thresh` is the minimum number of the received ACK + * eliciting packets that triggers the immediate acknowledgement. + */ + size_t ack_thresh; + /** + * :member:`no_tx_udp_payload_size_shaping`, if set to nonzero, + * instructs the library not to limit the UDP payload size to + * :macro:`NGTCP2_MAX_UDP_PAYLOAD_SIZE` (which can be extended by + * Path MTU Discovery) and instead use the mininum size among the + * given buffer size, :member:`max_tx_udp_payload_size`, and the + * received max_udp_payload QUIC transport parameter. + */ + int no_tx_udp_payload_size_shaping; + /** + * :member:`handshake_timeout` is the period of time before giving + * up QUIC connection establishment. If QUIC handshake is not + * complete within this period, `ngtcp2_conn_handle_expiry` returns + * :macro:`NGTCP2_ERR_HANDSHAKE_TIMEOUT` error. The deadline is + * :member:`initial_ts` + :member:`handshake_timeout`. If this + * field is set to ``UINT64_MAX``, no handshake timeout is set. + */ + ngtcp2_duration handshake_timeout; + /** + * :member:`preferred_versions` is the array of versions that are + * preferred by the local endpoint. All versions set in this array + * must be supported by the library, and compatible to QUIC v1. The + * reserved versions are not allowed. They are sorted in the order + * of preference. + * + * On compatible version negotiation, server will negotiate one of + * those versions contained in this array if there is some overlap + * between these versions and the versions offered by the client. + * If there is no overlap, but the client chosen version is + * supported by the library, the server chooses the client chosen + * version as the negotiated version. This version set corresponds + * to Offered Versions in QUIC Version Negotiation draft, and it + * should be included in Version Negotiation packet. + * + * Client uses this field and :member:`original_version` to prevent + * version downgrade attack if it reacted upon Version Negotiation + * packet. If this field is specified, client must include + * |client_chosen_version| passed to `ngtcp2_conn_client_new` unless + * |client_chosen_version| is a reserved version. + */ + const uint32_t *preferred_versions; + /** + * :member:`preferred_versionslen` is the number of versions that + * are contained in the array pointed by + * :member:`preferred_versions`. + */ + size_t preferred_versionslen; + /** + * :member:`available_versions` is the array of versions that are + * going to be set in :member:`available_versions + * <ngtcp2_version_info.available_versions>` field of outgoing + * version_information QUIC transport parameter. + * + * For server, this corresponds to Fully-Deployed Versions in QUIC + * Version Negotiation draft. If this field is set not, it is set + * to :member:`preferred_versions` internally if + * :member:`preferred_versionslen` is not zero. If this field is + * not set, and :member:`preferred_versionslen` is zero, this field + * is set to :macro:`NGTCP2_PROTO_VER_V1` internally. + * + * Client must include |client_chosen_version| passed to + * `ngtcp2_conn_client_new` in this array if this field is set and + * |client_chosen_version| is not a reserved version. If this field + * is not set, |client_chosen_version| passed to + * `ngtcp2_conn_client_new` will be set in this field internally + * unless |client_chosen_version| is a reserved version. + */ + const uint32_t *available_versions; + /** + * :member:`available_versionslen` is the number of versions that + * are contained in the array pointed by + * :member:`available_versions`. + */ + size_t available_versionslen; + /** + * :member:`original_version` is the original version that client + * initially used to make a connection attempt. If it is set, and + * it differs from |client_chosen_version| passed to + * `ngtcp2_conn_client_new`, the library assumes that client reacted + * upon Version Negotiation packet. Server does not use this field. + */ + uint32_t original_version; + /** + * :member:`no_pmtud`, if set to nonzero, disables Path MTU + * Discovery. + */ + int no_pmtud; +} ngtcp2_settings; + +/** + * @struct + * + * :type:`ngtcp2_addr` is the endpoint address. + */ +typedef struct ngtcp2_addr { + /** + * :member:`addr` points to the buffer which contains endpoint + * address. It must not be ``NULL``. + */ + ngtcp2_sockaddr *addr; + /** + * :member:`addrlen` is the length of addr. + */ + ngtcp2_socklen addrlen; +} ngtcp2_addr; + +/** + * @struct + * + * :type:`ngtcp2_path` is the network endpoints where a packet is sent + * and received. + */ +typedef struct ngtcp2_path { + /** + * :member:`local` is the address of local endpoint. + */ + ngtcp2_addr local; + /** + * :member:`remote` is the address of remote endpoint. + */ + ngtcp2_addr remote; + /** + * :member:`user_data` is an arbitrary data and opaque to the + * library. + * + * Note that :type:`ngtcp2_path` is generally passed to + * :type:`ngtcp2_conn` by an application, and :type:`ngtcp2_conn` + * stores their copies. Unfortunately, there is no way for the + * application to know when :type:`ngtcp2_conn` finishes using a + * specific :type:`ngtcp2_path` object in mid connection, which + * means that the application cannot free the data pointed by this + * field. Therefore, it is advised to use this field only when the + * data pointed by this field persists in an entire lifetime of the + * connection. + */ + void *user_data; +} ngtcp2_path; + +/** + * @struct + * + * :type:`ngtcp2_path_storage` is a convenient struct to have buffers + * to store the longest addresses. + */ +typedef struct ngtcp2_path_storage { + /** + * :member:`path` stores network path. + */ + ngtcp2_path path; + /** + * :member:`local_addrbuf` is a buffer to store local address. + */ + ngtcp2_sockaddr_union local_addrbuf; + /** + * :member:`remote_addrbuf` is a buffer to store remote address. + */ + ngtcp2_sockaddr_union remote_addrbuf; +} ngtcp2_path_storage; + +/** + * @struct + * + * :type:`ngtcp2_crypto_md` is a wrapper around native message digest + * object. + */ +typedef struct ngtcp2_crypto_md { + /** + * :member:`native_handle` is a pointer to an underlying message + * digest object. + */ + void *native_handle; +} ngtcp2_crypto_md; + +/** + * @struct + * + * :type:`ngtcp2_crypto_aead` is a wrapper around native AEAD object. + */ +typedef struct ngtcp2_crypto_aead { + /** + * :member:`native_handle` is a pointer to an underlying AEAD + * object. + */ + void *native_handle; + /** + * :member:`max_overhead` is the number of additional bytes which + * AEAD encryption needs on encryption. + */ + size_t max_overhead; +} ngtcp2_crypto_aead; + +/** + * @struct + * + * :type:`ngtcp2_crypto_cipher` is a wrapper around native cipher + * object. + */ +typedef struct ngtcp2_crypto_cipher { + /** + * :member:`native_handle` is a pointer to an underlying cipher + * object. + */ + void *native_handle; +} ngtcp2_crypto_cipher; + +/** + * @struct + * + * :type:`ngtcp2_crypto_aead_ctx` is a wrapper around native AEAD + * cipher context object. It should be initialized with a specific + * key. ngtcp2 library reuses this context object to encrypt or + * decrypt multiple packets. + */ +typedef struct ngtcp2_crypto_aead_ctx { + /** + * :member:`native_handle` is a pointer to an underlying AEAD + * context object. + */ + void *native_handle; +} ngtcp2_crypto_aead_ctx; + +/** + * @struct + * + * :type:`ngtcp2_crypto_cipher_ctx` is a wrapper around native cipher + * context object. It should be initialized with a specific key. + * ngtcp2 library reuses this context object to encrypt or decrypt + * multiple packet headers. + */ +typedef struct ngtcp2_crypto_cipher_ctx { + /** + * :member:`native_handle` is a pointer to an underlying cipher + * context object. + */ + void *native_handle; +} ngtcp2_crypto_cipher_ctx; + +/** + * @struct + * + * :type:`ngtcp2_crypto_ctx` is a convenient structure to bind all + * crypto related objects in one place. Use + * `ngtcp2_crypto_ctx_initial` to initialize this struct for Initial + * packet encryption. For Handshake and 1RTT packets, use + * `ngtcp2_crypto_ctx_tls`. + */ +typedef struct ngtcp2_crypto_ctx { + /** + * :member:`aead` is AEAD object. + */ + ngtcp2_crypto_aead aead; + /** + * :member:`md` is message digest object. + */ + ngtcp2_crypto_md md; + /** + * :member:`hp` is header protection cipher. + */ + ngtcp2_crypto_cipher hp; + /** + * :member:`max_encryption` is the number of encryption which this + * key can be used with. + */ + uint64_t max_encryption; + /** + * :member:`max_decryption_failure` is the number of decryption + * failure with this key. + */ + uint64_t max_decryption_failure; +} ngtcp2_crypto_ctx; + +/** + * @function + * + * `ngtcp2_encode_transport_params` encodes |params| in |dest| of + * length |destlen|. + * + * If |dest| is NULL, and |destlen| is zero, this function just + * returns the number of bytes required to store the encoded transport + * parameters. + * + * This function returns the number of written, or one of the + * following negative error codes: + * + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small. + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * |exttype| is invalid. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_encode_transport_params_versioned( + uint8_t *dest, size_t destlen, ngtcp2_transport_params_type exttype, + int transport_params_version, const ngtcp2_transport_params *params); + +/** + * @function + * + * `ngtcp2_decode_transport_params` decodes transport parameters in + * |data| of length |datalen|, and stores the result in the object + * pointed by |params|. + * + * If the optional parameters are missing, the default value is + * assigned. + * + * The following fields may point to somewhere inside the buffer + * pointed by |data| of length |datalen|: + * + * - :member:`ngtcp2_transport_params.version_info.available_versions + * <ngtcp2_version_info.available_versions>` + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_REQUIRED_TRANSPORT_PARAM` + * The required parameter is missing. + * :macro:`NGTCP2_ERR_MALFORMED_TRANSPORT_PARAM` + * The input is malformed. + */ +NGTCP2_EXTERN int ngtcp2_decode_transport_params_versioned( + int transport_params_version, ngtcp2_transport_params *params, + ngtcp2_transport_params_type exttype, const uint8_t *data, size_t datalen); + +/** + * @function + * + * `ngtcp2_decode_transport_params_new` decodes transport parameters + * in |data| of length |datalen|, and stores the result in the object + * allocated dynamically. The pointer to the allocated object is + * assigned to |*pparams|. Unlike `ngtcp2_decode_transport_params`, + * all direct and indirect fields are also allocated dynamically if + * needed. + * + * |mem| is a memory allocator to allocate memory. If |mem| is + * ``NULL``, the memory allocator returned by `ngtcp2_mem_default()` + * is used. + * + * If the optional parameters are missing, the default value is + * assigned. + * + * `ngtcp2_transport_params_del` frees the memory allocated by this + * function. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_REQUIRED_TRANSPORT_PARAM` + * The required parameter is missing. + * :macro:`NGTCP2_ERR_MALFORMED_TRANSPORT_PARAM` + * The input is malformed. + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_decode_transport_params_new( + ngtcp2_transport_params **pparams, ngtcp2_transport_params_type exttype, + const uint8_t *data, size_t datalen, const ngtcp2_mem *mem); + +/** + * @function + * + * `ngtcp2_transport_params_del` frees the |params| which must be + * dynamically allocated by `ngtcp2_decode_transport_params_new`. + * + * |mem| is a memory allocator that allocated |params|. If |mem| is + * ``NULL``, the memory allocator returned by `ngtcp2_mem_default()` + * is used. + * + * If |params| is ``NULL``, this function does nothing. + */ +NGTCP2_EXTERN void ngtcp2_transport_params_del(ngtcp2_transport_params *params, + const ngtcp2_mem *mem); + +/** + * @struct + * + * :type:`ngtcp2_version_cid` is a convenient struct to store the + * result of `ngtcp2_pkt_decode_version_cid`. + */ +typedef struct ngtcp2_version_cid { + /** + * :member:`version` stores QUIC version. + */ + uint32_t version; + /** + * :member:`dcid` points to the Destination Connection ID. + */ + const uint8_t *dcid; + /** + * :member:`dcidlen` is the length of the Destination Connection ID + * pointed by :member:`dcid`. + */ + size_t dcidlen; + /** + * :member:`scid` points to the Source Connection ID. + */ + const uint8_t *scid; + /** + * :member:`scidlen` is the length of the Source Connection ID + * pointed by :member:`scid`. + */ + size_t scidlen; +} ngtcp2_version_cid; + +/** + * @function + * + * `ngtcp2_pkt_decode_version_cid` extracts QUIC version, Destination + * Connection ID and Source Connection ID from the packet pointed by + * |data| of length |datalen|. This function can handle Connection ID + * up to 255 bytes unlike `ngtcp2_pkt_decode_hd_long` or + * `ngtcp2_pkt_decode_hd_short` which are only capable of handling + * Connection ID less than or equal to :macro:`NGTCP2_MAX_CIDLEN`. + * Longer Connection ID is only valid if the version is unsupported + * QUIC version. + * + * If the given packet is Long header packet, this function extracts + * the version from the packet and assigns it to + * :member:`dest->version <ngtcp2_version_cid.version>`. It also + * extracts the pointer to the Destination Connection ID and its + * length and assigns them to :member:`dest->dcid + * <ngtcp2_version_cid.dcid>` and :member:`dest->dcidlen + * <ngtcp2_version_cid.dcidlen>` respectively. Similarly, it extracts + * the pointer to the Source Connection ID and its length and assigns + * them to :member:`dest->scid <ngtcp2_version_cid.scid>` and + * :member:`dest->scidlen <ngtcp2_version_cid.scidlen>` respectively. + * + * If the given packet is Short header packet, :member:`dest->version + * <ngtcp2_version_cid.version>` will be 0, :member:`dest->scid + * <ngtcp2_version_cid.scid>` will be ``NULL``, and + * :member:`dest->scidlen <ngtcp2_version_cid.scidlen>` will be 0. + * Because the Short header packet does not have the length of + * Destination Connection ID, the caller has to pass the length in + * |short_dcidlen|. This function extracts the pointer to the + * Destination Connection ID and assigns it to :member:`dest->dcid + * <ngtcp2_version_cid.dcid>`. |short_dcidlen| is assigned to + * :member:`dest->dcidlen <ngtcp2_version_cid.dcidlen>`. + * + * If Version Negotiation is required, this function returns + * :macro:`NGTCP2_ERR_VERSION_NEGOTIATION`. Unlike the other error + * cases, all fields of |dest| are assigned as described above. + * + * This function returns 0 if it succeeds. Otherwise, one of the + * following negative error code: + * + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * The function could not decode the packet header. + * :macro:`NGTCP2_ERR_VERSION_NEGOTIATION` + * Version Negotiation packet should be sent. + */ +NGTCP2_EXTERN int ngtcp2_pkt_decode_version_cid(ngtcp2_version_cid *dest, + const uint8_t *data, + size_t datalen, + size_t short_dcidlen); + +/** + * @function + * + * `ngtcp2_pkt_decode_hd_long` decodes QUIC long packet header in + * |pkt| of length |pktlen|. This function only parses the input just + * before packet number field. + * + * This function does not verify that length field is correct. In + * other words, this function succeeds even if length > |pktlen|. + * + * This function can handle Connection ID up to + * :macro:`NGTCP2_MAX_CIDLEN`. Consider to use + * `ngtcp2_pkt_decode_version_cid` to get longer Connection ID. + * + * This function handles Version Negotiation specially. If version + * field is 0, |pkt| must contain Version Negotiation packet. Version + * Negotiation packet has random type in wire format. For + * convenience, this function sets + * :enum:`ngtcp2_pkt_type.NGTCP2_PKT_VERSION_NEGOTIATION` to + * :member:`dest->type <ngtcp2_pkt_hd.type>`, clears + * :macro:`NGTCP2_PKT_FLAG_LONG_FORM` flag from :member:`dest->flags + * <ngtcp2_pkt_hd.flags>`, and sets 0 to :member:`dest->len + * <ngtcp2_pkt_hd.len>`. Version Negotiation packet occupies a single + * packet. + * + * It stores the result in the object pointed by |dest|, and returns + * the number of bytes decoded to read the packet header if it + * succeeds, or one of the following error codes: + * + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * Packet is too short; or it is not a long header + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_pkt_decode_hd_long(ngtcp2_pkt_hd *dest, + const uint8_t *pkt, + size_t pktlen); + +/** + * @function + * + * `ngtcp2_pkt_decode_hd_short` decodes QUIC short header packet + * header in |pkt| of length |pktlen|. |dcidlen| is the length of + * DCID in packet header. Short header packet does not encode the + * length of connection ID, thus we need the input from the outside. + * This function only parses the input just before packet number + * field. This function can handle Connection ID up to + * :macro:`NGTCP2_MAX_CIDLEN`. Consider to use + * `ngtcp2_pkt_decode_version_cid` to get longer Connection ID. It + * stores the result in the object pointed by |dest|, and returns the + * number of bytes decoded to read the packet header if it succeeds, + * or one of the following error codes: + * + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * Packet is too short; or it is not a short header + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_pkt_decode_hd_short(ngtcp2_pkt_hd *dest, + const uint8_t *pkt, + size_t pktlen, + size_t dcidlen); + +/** + * @function + * + * `ngtcp2_pkt_write_stateless_reset` writes Stateless Reset packet in + * the buffer pointed by |dest| whose length is |destlen|. + * |stateless_reset_token| is a pointer to the Stateless Reset Token, + * and its length must be :macro:`NGTCP2_STATELESS_RESET_TOKENLEN` + * bytes long. |rand| specifies the random octets preceding Stateless + * Reset Token. The length of |rand| is specified by |randlen| which + * must be at least :macro:`NGTCP2_MIN_STATELESS_RESET_RANDLEN` bytes + * long. + * + * If |randlen| is too long to write them all in the buffer, |rand| is + * written to the buffer as much as possible, and is truncated. + * + * This function returns the number of bytes written to the buffer, or + * one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small. + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * |randlen| is strictly less than + * :macro:`NGTCP2_MIN_STATELESS_RESET_RANDLEN`. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_pkt_write_stateless_reset( + uint8_t *dest, size_t destlen, const uint8_t *stateless_reset_token, + const uint8_t *rand, size_t randlen); + +/** + * @function + * + * `ngtcp2_pkt_write_version_negotiation` writes Version Negotiation + * packet in the buffer pointed by |dest| whose length is |destlen|. + * |unused_random| should be generated randomly. |dcid| is the + * destination connection ID which appears in a packet as a source + * connection ID sent by client which caused version negotiation. + * Similarly, |scid| is the source connection ID which appears in a + * packet as a destination connection ID sent by client. |sv| is a + * list of supported versions, and |nsv| specifies the number of + * supported versions included in |sv|. + * + * This function returns the number of bytes written to the buffer, or + * one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_pkt_write_version_negotiation( + uint8_t *dest, size_t destlen, uint8_t unused_random, const uint8_t *dcid, + size_t dcidlen, const uint8_t *scid, size_t scidlen, const uint32_t *sv, + size_t nsv); + +/** + * @struct + * + * :type:`ngtcp2_conn` represents a single QUIC connection. + */ +typedef struct ngtcp2_conn ngtcp2_conn; + +/** + * @functypedef + * + * :type:`ngtcp2_client_initial` is invoked when client application + * asks TLS stack to produce first TLS cryptographic handshake data. + * + * This implementation of this callback must get the first handshake + * data from TLS stack and pass it to ngtcp2 library using + * `ngtcp2_conn_submit_crypto_data` function. Make sure that before + * calling `ngtcp2_conn_submit_crypto_data` function, client + * application must create initial packet protection keys and IVs, and + * provide them to ngtcp2 library using + * `ngtcp2_conn_install_initial_key`. + * + * This callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library call + * return immediately. + */ +typedef int (*ngtcp2_client_initial)(ngtcp2_conn *conn, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_recv_client_initial` is invoked when server receives + * Initial packet from client. An server application must implement + * this callback, and generate initial keys and IVs for both + * transmission and reception. Install them using + * `ngtcp2_conn_install_initial_key`. |dcid| is the destination + * connection ID which client generated randomly. It is used to + * derive initial packet protection keys. + * + * The callback function must return 0 if it succeeds. If an error + * occurs, return :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the + * library call return immediately. + */ +typedef int (*ngtcp2_recv_client_initial)(ngtcp2_conn *conn, + const ngtcp2_cid *dcid, + void *user_data); + +/** + * @enum + * + * :type:`ngtcp2_crypto_level` is encryption level. + */ +typedef enum ngtcp2_crypto_level { + /** + * :enum:`NGTCP2_CRYPTO_LEVEL_INITIAL` is Initial Keys encryption + * level. + */ + NGTCP2_CRYPTO_LEVEL_INITIAL, + /** + * :enum:`NGTCP2_CRYPTO_LEVEL_HANDSHAKE` is Handshake Keys + * encryption level. + */ + NGTCP2_CRYPTO_LEVEL_HANDSHAKE, + /** + * :enum:`NGTCP2_CRYPTO_LEVEL_APPLICATION` is Application Data + * (1-RTT) Keys encryption level. + */ + NGTCP2_CRYPTO_LEVEL_APPLICATION, + /** + * :enum:`NGTCP2_CRYPTO_LEVEL_EARLY` is Early Data (0-RTT) Keys + * encryption level. + */ + NGTCP2_CRYPTO_LEVEL_EARLY +} ngtcp2_crypto_level; + +/** + * @functypedef + * + * :type`ngtcp2_recv_crypto_data` is invoked when crypto data is + * received. The received data is pointed to by |data|, and its + * length is |datalen|. The |offset| specifies the offset where + * |data| is positioned. |user_data| is the arbitrary pointer passed + * to `ngtcp2_conn_client_new` or `ngtcp2_conn_server_new`. The + * ngtcp2 library ensures that the crypto data is passed to the + * application in the increasing order of |offset|. |datalen| is + * always strictly greater than 0. |crypto_level| indicates the + * encryption level where this data is received. Crypto data can + * never be received in + * :enum:`ngtcp2_crypto_level.NGTCP2_CRYPTO_LEVEL_EARLY`. + * + * The application should provide the given data to TLS stack. + * + * The callback function must return 0 if it succeeds, or one of the + * following negative error codes: + * + * - :macro:`NGTCP2_ERR_CRYPTO` + * - :macro:`NGTCP2_ERR_REQUIRED_TRANSPORT_PARAM` + * - :macro:`NGTCP2_ERR_MALFORMED_TRANSPORT_PARAM` + * - :macro:`NGTCP2_ERR_TRANSPORT_PARAM` + * - :macro:`NGTCP2_ERR_PROTO` + * - :macro:`NGTCP2_ERR_VERSION_NEGOTIATION_FAILURE` + * - :macro:`NGTCP2_ERR_NOMEM` + * - :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * + * If the other value is returned, it is treated as + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE`. + * + * If application encounters fatal error, return + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library call + * return immediately. + */ +typedef int (*ngtcp2_recv_crypto_data)(ngtcp2_conn *conn, + ngtcp2_crypto_level crypto_level, + uint64_t offset, const uint8_t *data, + size_t datalen, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_handshake_completed` is invoked when QUIC + * cryptographic handshake has completed. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_handshake_completed)(ngtcp2_conn *conn, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_handshake_confirmed` is invoked when QUIC + * cryptographic handshake is confirmed. The handshake confirmation + * means that both endpoints agree that handshake has finished. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_handshake_confirmed)(ngtcp2_conn *conn, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_recv_version_negotiation` is invoked when Version + * Negotiation packet is received. |hd| is the pointer to the QUIC + * packet header object. The vector |sv| of |nsv| elements contains + * the QUIC version the server supports. Since Version Negotiation is + * only sent by server, this callback function is used by client only. + * + * The callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library call + * return immediately. + */ +typedef int (*ngtcp2_recv_version_negotiation)(ngtcp2_conn *conn, + const ngtcp2_pkt_hd *hd, + const uint32_t *sv, size_t nsv, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_recv_retry` is invoked when Retry packet is received. + * This callback is client use only. + * + * Application must regenerate packet protection key, IV, and header + * protection key for Initial packets using the destination connection + * ID obtained by :member:`hd->scid <ngtcp2_pkt_hd.scid>` and install + * them by calling `ngtcp2_conn_install_initial_key()`. + * + * 0-RTT data accepted by the ngtcp2 library will be automatically + * retransmitted as 0-RTT data by the library. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_recv_retry)(ngtcp2_conn *conn, const ngtcp2_pkt_hd *hd, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_encrypt` is invoked when the ngtcp2 library asks the + * application to encrypt packet payload. The packet payload to + * encrypt is passed as |plaintext| of length |plaintextlen|. The + * AEAD cipher is |aead|. |aead_ctx| is the AEAD cipher context + * object which is initialized with encryption key. The nonce is + * passed as |nonce| of length |noncelen|. The Additional + * Authenticated Data is passed as |aad| of length |aadlen|. + * + * The implementation of this callback must encrypt |plaintext| using + * the negotiated cipher suite and write the ciphertext into the + * buffer pointed by |dest|. |dest| has enough capacity to store the + * ciphertext and any additional AEAD tag data. + * + * |dest| and |plaintext| may point to the same buffer. + * + * The callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library call + * return immediately. + */ +typedef int (*ngtcp2_encrypt)(uint8_t *dest, const ngtcp2_crypto_aead *aead, + const ngtcp2_crypto_aead_ctx *aead_ctx, + const uint8_t *plaintext, size_t plaintextlen, + const uint8_t *nonce, size_t noncelen, + const uint8_t *aad, size_t aadlen); + +/** + * @functypedef + * + * :type:`ngtcp2_decrypt` is invoked when the ngtcp2 library asks the + * application to decrypt packet payload. The packet payload to + * decrypt is passed as |ciphertext| of length |ciphertextlen|. The + * AEAD cipher is |aead|. |aead_ctx| is the AEAD cipher context + * object which is initialized with decryption key. The nonce is + * passed as |nonce| of length |noncelen|. The Additional + * Authenticated Data is passed as |aad| of length |aadlen|. + * + * The implementation of this callback must decrypt |ciphertext| using + * the negotiated cipher suite and write the ciphertext into the + * buffer pointed by |dest|. |dest| has enough capacity to store the + * cleartext. + * + * |dest| and |ciphertext| may point to the same buffer. + * + * The callback function must return 0 if it succeeds. If TLS stack + * fails to decrypt data, return :macro:`NGTCP2_ERR_DECRYPT`. For any + * other errors, return :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which + * makes the library call return immediately. + */ +typedef int (*ngtcp2_decrypt)(uint8_t *dest, const ngtcp2_crypto_aead *aead, + const ngtcp2_crypto_aead_ctx *aead_ctx, + const uint8_t *ciphertext, size_t ciphertextlen, + const uint8_t *nonce, size_t noncelen, + const uint8_t *aad, size_t aadlen); + +/** + * @functypedef + * + * :type:`ngtcp2_hp_mask` is invoked when the ngtcp2 library asks the + * application to produce a mask to encrypt or decrypt packet header. + * The encryption cipher is |hp|. |hp_ctx| is the cipher context + * object which is initialized with header protection key. The sample + * is passed as |sample| which is :macro:`NGTCP2_HP_SAMPLELEN` bytes + * long. + * + * The implementation of this callback must produce a mask using the + * header protection cipher suite specified by QUIC specification and + * write the result into the buffer pointed by |dest|. The length of + * the mask must be at least :macro:`NGTCP2_HP_MASKLEN`. The library + * only uses the first :macro:`NGTCP2_HP_MASKLEN` bytes of the + * produced mask. The buffer pointed by |dest| is guaranteed to have + * at least :macro:`NGTCP2_HP_SAMPLELEN` bytes available for + * convenience. + * + * The callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library call + * return immediately. + */ +typedef int (*ngtcp2_hp_mask)(uint8_t *dest, const ngtcp2_crypto_cipher *hp, + const ngtcp2_crypto_cipher_ctx *hp_ctx, + const uint8_t *sample); + +/** + * @macrosection + * + * Stream data flags + */ + +/** + * @macro + * + * :macro:`NGTCP2_STREAM_DATA_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_STREAM_DATA_FLAG_NONE 0x00u + +/** + * @macro + * + * :macro:`NGTCP2_STREAM_DATA_FLAG_FIN` indicates that this chunk of + * data is final piece of an incoming stream. + */ +#define NGTCP2_STREAM_DATA_FLAG_FIN 0x01u + +/** + * @macro + * + * :macro:`NGTCP2_STREAM_DATA_FLAG_EARLY` indicates that this chunk of + * data contains data received in 0RTT packet and the handshake has + * not completed yet, which means that the data might be replayed. + */ +#define NGTCP2_STREAM_DATA_FLAG_EARLY 0x02u + +/** + * @functypedef + * + * :type:`ngtcp2_recv_stream_data` is invoked when stream data is + * received. The stream is specified by |stream_id|. |flags| is the + * bitwise-OR of zero or more of :macro:`NGTCP2_STREAM_DATA_FLAG_* + * <NGTCP2_STREAM_DATA_FLAG_NONE>`. If |flags| & + * :macro:`NGTCP2_STREAM_DATA_FLAG_FIN` is nonzero, this portion of + * the data is the last data in this stream. |offset| is the offset + * where this data begins. The library ensures that data is passed to + * the application in the non-decreasing order of |offset| without any + * overlap. The data is passed as |data| of length |datalen|. + * |datalen| may be 0 if and only if |fin| is nonzero. + * + * If :macro:`NGTCP2_STREAM_DATA_FLAG_EARLY` is set in |flags|, it + * indicates that a part of or whole data was received in 0RTT packet + * and a handshake has not completed yet. + * + * The callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library return + * immediately. + */ +typedef int (*ngtcp2_recv_stream_data)(ngtcp2_conn *conn, uint32_t flags, + int64_t stream_id, uint64_t offset, + const uint8_t *data, size_t datalen, + void *user_data, void *stream_user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_stream_open` is a callback function which is called + * when remote stream is opened by peer. This function is not called + * if stream is opened by implicitly (we might reconsider this + * behaviour). + * + * The implementation of this callback should return 0 if it succeeds. + * Returning :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library + * call return immediately. + */ +typedef int (*ngtcp2_stream_open)(ngtcp2_conn *conn, int64_t stream_id, + void *user_data); + +/** + * @macrosection + * + * Stream close flags + */ + +/** + * @macro + * + * :macro:`NGTCP2_STREAM_CLOSE_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_STREAM_CLOSE_FLAG_NONE 0x00u + +/** + * @macro + * + * :macro:`NGTCP2_STREAM_CLOSE_FLAG_APP_ERROR_CODE_SET` indicates that + * app_error_code parameter is set. + */ +#define NGTCP2_STREAM_CLOSE_FLAG_APP_ERROR_CODE_SET 0x01u + +/** + * @functypedef + * + * :type:`ngtcp2_stream_close` is invoked when a stream is closed. + * This callback is not called when QUIC connection is closed before + * existing streams are closed. |flags| is the bitwise-OR of zero or + * more of :macro:`NGTCP2_STREAM_CLOSE_FLAG_* + * <NGTCP2_STREAM_CLOSE_FLAG_NONE>`. |app_error_code| indicates the + * error code of this closure if + * :macro:`NGTCP2_STREAM_CLOSE_FLAG_APP_ERROR_CODE_SET` is set in + * |flags|. If it is not set, the stream was closed without any error + * code, which generally means success. + * + * |app_error_code| is the first application error code sent by a + * local endpoint, or received from a remote endpoint. If a stream is + * closed cleanly, no application error code is exchanged. Since QUIC + * stack does not know the application error code which indicates "no + * errors", |app_error_code| is set to 0 and + * :macro:`NGTCP2_STREAM_CLOSE_FLAG_APP_ERROR_CODE_SET` is not set in + * |flags| in this case. + * + * The implementation of this callback should return 0 if it succeeds. + * Returning :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library + * call return immediately. + */ +typedef int (*ngtcp2_stream_close)(ngtcp2_conn *conn, uint32_t flags, + int64_t stream_id, uint64_t app_error_code, + void *user_data, void *stream_user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_stream_reset` is invoked when a stream identified by + * |stream_id| is reset by a remote endpoint. + * + * The implementation of this callback should return 0 if it succeeds. + * Returning :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library + * call return immediately. + */ +typedef int (*ngtcp2_stream_reset)(ngtcp2_conn *conn, int64_t stream_id, + uint64_t final_size, uint64_t app_error_code, + void *user_data, void *stream_user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_acked_stream_data_offset` is a callback function + * which is called when stream data is acked, and application can free + * the data. The acked range of data is [offset, offset + datalen). + * For a given stream_id, this callback is called sequentially in + * increasing order of |offset| without any overlap. |datalen| is + * normally strictly greater than 0. One exception is that when a + * packet which includes STREAM frame which has fin flag set, and 0 + * length data, this callback is invoked with 0 passed as |datalen|. + * + * If a stream is closed prematurely and stream data is still + * in-flight, this callback function is not called for those data. + * + * The implementation of this callback should return 0 if it succeeds. + * Returning :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library + * call return immediately. + */ +typedef int (*ngtcp2_acked_stream_data_offset)( + ngtcp2_conn *conn, int64_t stream_id, uint64_t offset, uint64_t datalen, + void *user_data, void *stream_user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_recv_stateless_reset` is a callback function which is + * called when Stateless Reset packet is received. The stateless + * reset details are given in |sr|. + * + * The implementation of this callback should return 0 if it succeeds. + * Returning :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library + * call return immediately. + */ +typedef int (*ngtcp2_recv_stateless_reset)(ngtcp2_conn *conn, + const ngtcp2_pkt_stateless_reset *sr, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_extend_max_streams` is a callback function which is + * called every time max stream ID is strictly extended. + * |max_streams| is the cumulative number of streams which an endpoint + * can open. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_extend_max_streams)(ngtcp2_conn *conn, + uint64_t max_streams, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_extend_max_stream_data` is a callback function which + * is invoked when max stream data is extended. |stream_id| + * identifies the stream. |max_data| is a cumulative number of bytes + * the endpoint can send on this stream. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_extend_max_stream_data)(ngtcp2_conn *conn, + int64_t stream_id, + uint64_t max_data, void *user_data, + void *stream_user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_rand` is a callback function to get randomized byte + * string from application. Application must fill random |destlen| + * bytes to the buffer pointed by |dest|. The generated bytes are + * used only in non-cryptographic context. + */ +typedef void (*ngtcp2_rand)(uint8_t *dest, size_t destlen, + const ngtcp2_rand_ctx *rand_ctx); + +/** + * @functypedef + * + * :type:`ngtcp2_get_new_connection_id` is a callback function to ask + * an application for new connection ID. Application must generate + * new unused connection ID with the exact |cidlen| bytes and store it + * in |cid|. It also has to generate stateless reset token into + * |token|. The length of stateless reset token is + * :macro:`NGTCP2_STATELESS_RESET_TOKENLEN` and it is guaranteed that + * the buffer pointed by |cid| has the sufficient space to store the + * token. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_get_new_connection_id)(ngtcp2_conn *conn, ngtcp2_cid *cid, + uint8_t *token, size_t cidlen, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_remove_connection_id` is a callback function which + * notifies the application that connection ID |cid| is no longer used + * by remote endpoint. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_remove_connection_id)(ngtcp2_conn *conn, + const ngtcp2_cid *cid, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_update_key` is a callback function which tells the + * application that it must generate new packet protection keying + * materials and AEAD cipher context objects with new keys. The + * current set of secrets are given as |current_rx_secret| and + * |current_tx_secret| of length |secretlen|. They are decryption and + * encryption secrets respectively. + * + * The application has to generate new secrets and keys for both + * encryption and decryption, and write decryption secret and IV to + * the buffer pointed by |rx_secret| and |rx_iv| respectively. It + * also has to create new AEAD cipher context object with new + * decryption key and initialize |rx_aead_ctx| with it. Similarly, + * write encryption secret and IV to the buffer pointed by |tx_secret| + * and |tx_iv|. Create new AEAD cipher context object with new + * encryption key and initialize |tx_aead_ctx| with it. All given + * buffers have the enough capacity to store secret, key and IV. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_update_key)( + ngtcp2_conn *conn, uint8_t *rx_secret, uint8_t *tx_secret, + ngtcp2_crypto_aead_ctx *rx_aead_ctx, uint8_t *rx_iv, + ngtcp2_crypto_aead_ctx *tx_aead_ctx, uint8_t *tx_iv, + const uint8_t *current_rx_secret, const uint8_t *current_tx_secret, + size_t secretlen, void *user_data); + +/** + * @macrosection + * + * Path validation related macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_PATH_VALIDATION_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_PATH_VALIDATION_FLAG_NONE 0x00u + +/** + * @macro + * + * :macro:`NGTCP2_PATH_VALIDATION_FLAG_PREFERRED_ADDR` indicates the + * validation involving server preferred address. This flag is only + * set for client. + */ +#define NGTCP2_PATH_VALIDATION_FLAG_PREFERRED_ADDR 0x01u + +/** + * @functypedef + * + * :type:`ngtcp2_path_validation` is a callback function which tells + * the application the outcome of path validation. |flags| is zero or + * more of :macro:`NGTCP2_PATH_VALIDATION_FLAG_* + * <NGTCP2_PATH_VALIDATION_FLAG_NONE>`. |path| is the path that was + * validated. If |res| is + * :enum:`ngtcp2_path_validation_result.NGTCP2_PATH_VALIDATION_RESULT_SUCCESS`, + * the path validation succeeded. If |res| is + * :enum:`ngtcp2_path_validation_result.NGTCP2_PATH_VALIDATION_RESULT_FAILURE`, + * the path validation failed. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_path_validation)(ngtcp2_conn *conn, uint32_t flags, + const ngtcp2_path *path, + ngtcp2_path_validation_result res, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_select_preferred_addr` is a callback function which + * asks a client application to choose server address from preferred + * addresses |paddr| received from server. An application should + * write a network path for a selected preferred address in |dest|. + * More specifically, the selected preferred address must be set to + * :member:`dest->remote <ngtcp2_path.remote>`, a client source + * address must be set to :member:`dest->local <ngtcp2_path.local>`. + * If a client source address does not change for the new server + * address, leave :member:`dest->local <ngtcp2_path.local>` + * unmodified, or copy the value of :member:`local + * <ngtcp2_path.local>` field of the current network path obtained + * from `ngtcp2_conn_get_path()`. Both :member:`dest->local.addr + * <ngtcp2_addr.addr>` and :member:`dest->remote.addr + * <ngtcp2_addr.addr>` point to buffers which are at least + * ``sizeof(struct sockaddr_storage)`` bytes long, respectively. If + * an application denies the preferred addresses, just leave |dest| + * unmodified (or set :member:`dest->remote.addrlen + * <ngtcp2_addr.addrlen>` to 0) and return 0. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_select_preferred_addr)(ngtcp2_conn *conn, + ngtcp2_path *dest, + const ngtcp2_preferred_addr *paddr, + void *user_data); + +/** + * @enum + * + * :type:`ngtcp2_connection_id_status_type` defines a set of status + * for Destination Connection ID. + */ +typedef enum ngtcp2_connection_id_status_type { + /** + * :enum:`NGTCP2_CONNECTION_ID_STATUS_TYPE_ACTIVATE` indicates that + * a local endpoint starts using new destination Connection ID. + */ + NGTCP2_CONNECTION_ID_STATUS_TYPE_ACTIVATE, + /** + * :enum:`NGTCP2_CONNECTION_ID_STATUS_TYPE_DEACTIVATE` indicates + * that a local endpoint stops using a given destination Connection + * ID. + */ + NGTCP2_CONNECTION_ID_STATUS_TYPE_DEACTIVATE +} ngtcp2_connection_id_status_type; + +/** + * @functypedef + * + * :type:`ngtcp2_connection_id_status` is a callback function which is + * called when the status of Connection ID changes. + * + * |token| is the associated stateless reset token and it is ``NULL`` + * if no token is present. + * + * |type| is the one of the value defined in + * :type:`ngtcp2_connection_id_status_type`. The new value might be + * added in the future release. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_connection_id_status)(ngtcp2_conn *conn, int type, + uint64_t seq, const ngtcp2_cid *cid, + const uint8_t *token, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_recv_new_token` is a callback function which is + * called when new token is received from server. + * + * |token| is the received token of length |tokenlen| bytes long. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_recv_new_token)(ngtcp2_conn *conn, const uint8_t *token, + size_t tokenlen, void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_delete_crypto_aead_ctx` is a callback function which + * must delete the native object pointed by + * :member:`aead_ctx->native_handle + * <ngtcp2_crypto_aead_ctx.native_handle>`. + */ +typedef void (*ngtcp2_delete_crypto_aead_ctx)(ngtcp2_conn *conn, + ngtcp2_crypto_aead_ctx *aead_ctx, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_delete_crypto_cipher_ctx` is a callback function + * which must delete the native object pointed by + * :member:`cipher_ctx->native_handle + * <ngtcp2_crypto_cipher_ctx.native_handle>`. + */ +typedef void (*ngtcp2_delete_crypto_cipher_ctx)( + ngtcp2_conn *conn, ngtcp2_crypto_cipher_ctx *cipher_ctx, void *user_data); + +/** + * @macrosection + * + * Datagram flags + */ + +/** + * @macro + * + * :macro:`NGTCP2_DATAGRAM_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_DATAGRAM_FLAG_NONE 0x00u + +/** + * @macro + * + * :macro:`NGTCP2_DATAGRAM_FLAG_EARLY` indicates that DATAGRAM frame + * is received in 0RTT packet and the handshake has not completed yet, + * which means that the data might be replayed. + */ +#define NGTCP2_DATAGRAM_FLAG_EARLY 0x01u + +/** + * @functypedef + * + * :type:`ngtcp2_recv_datagram` is invoked when DATAGRAM frame is + * received. |flags| is bitwise-OR of zero or more of + * :macro:`NGTCP2_DATAGRAM_FLAG_* <NGTCP2_DATAGRAM_FLAG_NONE>`. + * + * If :macro:`NGTCP2_DATAGRAM_FLAG_EARLY` is set in |flags|, it + * indicates that DATAGRAM frame was received in 0RTT packet and a + * handshake has not completed yet. + * + * The callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library return + * immediately. + */ +typedef int (*ngtcp2_recv_datagram)(ngtcp2_conn *conn, uint32_t flags, + const uint8_t *data, size_t datalen, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_ack_datagram` is invoked when a packet which contains + * DATAGRAM frame which is identified by |dgram_id| is acknowledged. + * |dgram_id| is the valued passed to `ngtcp2_conn_writev_datagram`. + * + * The callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library return + * immediately. + */ +typedef int (*ngtcp2_ack_datagram)(ngtcp2_conn *conn, uint64_t dgram_id, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_lost_datagram` is invoked when a packet which + * contains DATAGRAM frame which is identified by |dgram_id| is + * declared lost. |dgram_id| is the valued passed to + * `ngtcp2_conn_writev_datagram`. Note that the loss might be + * spurious, and DATAGRAM frame might be acknowledged later. + * + * The callback function must return 0 if it succeeds, or + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` which makes the library return + * immediately. + */ +typedef int (*ngtcp2_lost_datagram)(ngtcp2_conn *conn, uint64_t dgram_id, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_get_path_challenge_data` is a callback function to + * ask an application for new data that is sent in PATH_CHALLENGE + * frame. Application must generate new unpredictable exactly + * :macro:`NGTCP2_PATH_CHALLENGE_DATALEN` bytes of random data and + * store them into the buffer pointed by |data|. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_get_path_challenge_data)(ngtcp2_conn *conn, uint8_t *data, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_stream_stop_sending` is invoked when a stream is no + * longer read by a local endpoint before it receives all stream data. + * This function is called at most once per stream. |app_error_code| + * is the error code passed to `ngtcp2_conn_shutdown_stream_read` or + * `ngtcp2_conn_shutdown_stream`. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_stream_stop_sending)(ngtcp2_conn *conn, int64_t stream_id, + uint64_t app_error_code, + void *user_data, + void *stream_user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_version_negotiation` is invoked when the compatible + * version negotiation takes place. For client, it is called when it + * sees a change in version field of a long header packet. This + * callback function might be called multiple times for client. For + * server, it is called once when the version is negotiated. + * + * The implementation of this callback must install new Initial keys + * for |version|. Use `ngtcp2_conn_install_vneg_initial_key` to + * install keys. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_version_negotiation)(ngtcp2_conn *conn, uint32_t version, + const ngtcp2_cid *client_dcid, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_recv_key` is invoked when new key is installed to + * |conn| during QUIC cryptographic handshake. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_recv_key)(ngtcp2_conn *conn, ngtcp2_crypto_level level, + void *user_data); + +/** + * @functypedef + * + * :type:`ngtcp2_early_data_rejected` is invoked when early data was + * rejected by server, or client decided not to attempt early data. + * + * The callback function must return 0 if it succeeds. Returning + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` makes the library call return + * immediately. + */ +typedef int (*ngtcp2_early_data_rejected)(ngtcp2_conn *conn, void *user_data); + +#define NGTCP2_CALLBACKS_VERSION_V1 1 +#define NGTCP2_CALLBACKS_VERSION NGTCP2_CALLBACKS_VERSION_V1 + +/** + * @struct + * + * :type:`ngtcp2_callbacks` holds a set of callback functions. + */ +typedef struct ngtcp2_callbacks { + /** + * :member:`client_initial` is a callback function which is invoked + * when client asks TLS stack to produce first TLS cryptographic + * handshake message. This callback function must be specified for + * a client application. + */ + ngtcp2_client_initial client_initial; + /** + * :member:`recv_client_initial` is a callback function which is + * invoked when a server receives the first packet from client. + * This callback function must be specified for a server application. + */ + ngtcp2_recv_client_initial recv_client_initial; + /** + * :member:`recv_crypto_data` is a callback function which is + * invoked when cryptographic data (CRYPTO frame, in other words, + * TLS message) is received. This callback function must be + * specified. + */ + ngtcp2_recv_crypto_data recv_crypto_data; + /** + * :member:`handshake_completed` is a callback function which is + * invoked when QUIC cryptographic handshake has completed. This + * callback function is optional. + */ + ngtcp2_handshake_completed handshake_completed; + /** + * :member:`recv_version_negotiation` is a callback function which + * is invoked when Version Negotiation packet is received by a + * client. This callback function is optional. + */ + ngtcp2_recv_version_negotiation recv_version_negotiation; + /** + * :member:`encrypt` is a callback function which is invoked to + * encrypt a QUIC packet. This callback function must be specified. + */ + ngtcp2_encrypt encrypt; + /** + * :member:`decrypt` is a callback function which is invoked to + * decrypt a QUIC packet. This callback function must be specified. + */ + ngtcp2_decrypt decrypt; + /** + * :member:`hp_mask` is a callback function which is invoked to get + * a mask to encrypt or decrypt packet header. This callback + * function must be specified. + */ + ngtcp2_hp_mask hp_mask; + /** + * :member:`recv_stream_data` is a callback function which is + * invoked when STREAM data, which includes application data, is + * received. This callback function is optional. + */ + ngtcp2_recv_stream_data recv_stream_data; + /** + * :member:`acked_stream_data_offset` is a callback function which + * is invoked when STREAM data, which includes application data, is + * acknowledged by a remote endpoint. It tells an application the + * largest offset of acknowledged STREAM data without a gap so that + * application can free memory for the data. This callback function + * is optional. + */ + ngtcp2_acked_stream_data_offset acked_stream_data_offset; + /** + * :member:`stream_open` is a callback function which is invoked + * when new remote stream is opened by a remote endpoint. This + * callback function is optional. + */ + ngtcp2_stream_open stream_open; + /** + * :member:`stream_close` is a callback function which is invoked + * when a stream is closed. This callback function is optional. + */ + ngtcp2_stream_close stream_close; + /** + * :member:`recv_stateless_reset` is a callback function which is + * invoked when Stateless Reset packet is received. This callback + * function is optional. + */ + ngtcp2_recv_stateless_reset recv_stateless_reset; + /** + * :member:`recv_retry` is a callback function which is invoked when + * a client receives Retry packet. For client, this callback + * function must be specified. Server never receive Retry packet. + */ + ngtcp2_recv_retry recv_retry; + /** + * :member:`extend_max_local_streams_bidi` is a callback function + * which is invoked when the number of bidirectional stream which a + * local endpoint can open is increased. This callback function is + * optional. + */ + ngtcp2_extend_max_streams extend_max_local_streams_bidi; + /** + * :member:`extend_max_local_streams_uni` is a callback function + * which is invoked when the number of unidirectional stream which a + * local endpoint can open is increased. This callback function is + * optional. + */ + ngtcp2_extend_max_streams extend_max_local_streams_uni; + /** + * :member:`rand` is a callback function which is invoked when the + * library needs sequence of random data. This callback function + * must be specified. + */ + ngtcp2_rand rand; + /** + * :member:`get_new_connection_id` is a callback function which is + * invoked when the library needs new connection ID. This callback + * function must be specified. + */ + ngtcp2_get_new_connection_id get_new_connection_id; + /** + * :member:`remove_connection_id` is a callback function which + * notifies an application that connection ID is no longer used by a + * remote endpoint. This callback function is optional. + */ + ngtcp2_remove_connection_id remove_connection_id; + /** + * :member:`update_key` is a callback function which is invoked when + * the library tells an application that it must update keying + * materials and install new keys. This callback function must be + * specified. + */ + ngtcp2_update_key update_key; + /** + * :member:`path_validation` is a callback function which is invoked + * when path validation completed. This callback function is + * optional. + */ + ngtcp2_path_validation path_validation; + /** + * :member:`select_preferred_addr` is a callback function which is + * invoked when the library asks a client to select preferred + * address presented by a server. This callback function is + * optional. + */ + ngtcp2_select_preferred_addr select_preferred_addr; + /** + * :member:`stream_reset` is a callback function which is invoked + * when a stream is reset by a remote endpoint. This callback + * function is optional. + */ + ngtcp2_stream_reset stream_reset; + /** + * :member:`extend_max_remote_streams_bidi` is a callback function + * which is invoked when the number of bidirectional streams which a + * remote endpoint can open is increased. This callback function is + * optional. + */ + ngtcp2_extend_max_streams extend_max_remote_streams_bidi; + /** + * :member:`extend_max_remote_streams_uni` is a callback function + * which is invoked when the number of unidirectional streams which + * a remote endpoint can open is increased. This callback function + * is optional. + */ + ngtcp2_extend_max_streams extend_max_remote_streams_uni; + /** + * :member:`extend_max_stream_data` is callback function which is + * invoked when the maximum offset of STREAM data that a local + * endpoint can send is increased. This callback function is + * optional. + */ + ngtcp2_extend_max_stream_data extend_max_stream_data; + /** + * :member:`dcid_status` is a callback function which is invoked + * when the new destination Connection ID is activated or the + * activated destination Connection ID is now deactivated. This + * callback function is optional. + */ + ngtcp2_connection_id_status dcid_status; + /** + * :member:`handshake_confirmed` is a callback function which is + * invoked when both endpoints agree that handshake has finished. + * This field is ignored by server because handshake_completed + * indicates the handshake confirmation for server. This callback + * function is optional. + */ + ngtcp2_handshake_confirmed handshake_confirmed; + /** + * :member:`recv_new_token` is a callback function which is invoked + * when new token is received from server. This field is ignored by + * server. This callback function is optional. + */ + ngtcp2_recv_new_token recv_new_token; + /** + * :member:`delete_crypto_aead_ctx` is a callback function which + * deletes a given AEAD cipher context object. This callback + * function must be specified. + */ + ngtcp2_delete_crypto_aead_ctx delete_crypto_aead_ctx; + /** + * :member:`delete_crypto_cipher_ctx` is a callback function which + * deletes a given cipher context object. This callback function + * must be specified. + */ + ngtcp2_delete_crypto_cipher_ctx delete_crypto_cipher_ctx; + /** + * :member:`recv_datagram` is a callback function which is invoked + * when DATAGRAM frame is received. This callback function is + * optional. + */ + ngtcp2_recv_datagram recv_datagram; + /** + * :member:`ack_datagram` is a callback function which is invoked + * when a packet containing DATAGRAM frame is acknowledged. This + * callback function is optional. + */ + ngtcp2_ack_datagram ack_datagram; + /** + * :member:`lost_datagram` is a callback function which is invoked + * when a packet containing DATAGRAM frame is declared lost. This + * callback function is optional. + */ + ngtcp2_lost_datagram lost_datagram; + /** + * :member:`get_path_challenge_data` is a callback function which is + * invoked when the library needs new PATH_CHALLENGE data. This + * callback must be specified. + */ + ngtcp2_get_path_challenge_data get_path_challenge_data; + /** + * :member:`stream_stop_sending` is a callback function which is + * invoked when a local endpoint no longer reads from a stream + * before it receives all stream data. This callback function is + * optional. + */ + ngtcp2_stream_stop_sending stream_stop_sending; + /** + * :member:`version_negotiation` is a callback function which is + * invoked when the compatible version negotiation takes place. + * This callback function must be specified. + */ + ngtcp2_version_negotiation version_negotiation; + /** + * :member:`recv_rx_key` is a callback function which is invoked + * when a new key for decrypting packets is installed during QUIC + * cryptographic handshake. It is not called for + * :enum:`ngtcp2_crypto_level.NGTCP2_CRYPTO_LEVEL_INITIAL`. + */ + ngtcp2_recv_key recv_rx_key; + /** + * :member:`recv_tx_key` is a callback function which is invoked + * when a new key for encrypting packets is installed during QUIC + * cryptographic handshake. It is not called for + * :enum:`ngtcp2_crypto_level.NGTCP2_CRYPTO_LEVEL_INITIAL`. + */ + ngtcp2_recv_key recv_tx_key; + /** + * :member:`ngtcp2_early_data_rejected` is a callback function which + * is invoked when an attempt to send early data by client was + * rejected by server, or client decided not to attempt early data. + * This callback function is only used by client. + */ + ngtcp2_early_data_rejected early_data_rejected; +} ngtcp2_callbacks; + +/** + * @function + * + * `ngtcp2_pkt_write_connection_close` writes Initial packet + * containing CONNECTION_CLOSE frame with the given |error_code| and + * the optional |reason| of length |reasonlen| to the buffer pointed + * by |dest| of length |destlen|. All encryption parameters are for + * Initial packet encryption. The packet number is always 0. + * + * The primary use case of this function is for server to send + * CONNECTION_CLOSE frame in Initial packet to close connection + * without committing the state when validating Retry token fails. + * + * This function returns the number of bytes written if it succeeds, + * or one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * Callback function failed. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_pkt_write_connection_close( + uint8_t *dest, size_t destlen, uint32_t version, const ngtcp2_cid *dcid, + const ngtcp2_cid *scid, uint64_t error_code, const uint8_t *reason, + size_t reasonlen, ngtcp2_encrypt encrypt, const ngtcp2_crypto_aead *aead, + const ngtcp2_crypto_aead_ctx *aead_ctx, const uint8_t *iv, + ngtcp2_hp_mask hp_mask, const ngtcp2_crypto_cipher *hp, + const ngtcp2_crypto_cipher_ctx *hp_ctx); + +/** + * @function + * + * `ngtcp2_pkt_write_retry` writes Retry packet in the buffer pointed + * by |dest| whose length is |destlen|. |dcid| is the destination + * connection ID which appeared in a packet as a source connection ID + * sent by client. |scid| is a server chosen source connection ID. + * |odcid| specifies Original Destination Connection ID which appeared + * in a packet as a destination connection ID sent by client. |token| + * specifies Retry Token, and |tokenlen| specifies its length. |aead| + * must be AEAD_AES_128_GCM. |aead_ctx| must be initialized with + * :macro:`NGTCP2_RETRY_KEY` as an encryption key. + * + * This function returns the number of bytes written to the buffer, or + * one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * Callback function failed. + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * :member:`odcid->datalen <ngtcp2_cid.datalen>` is less than + * :macro:`NGTCP2_MIN_INITIAL_DCIDLEN`. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_pkt_write_retry( + uint8_t *dest, size_t destlen, uint32_t version, const ngtcp2_cid *dcid, + const ngtcp2_cid *scid, const ngtcp2_cid *odcid, const uint8_t *token, + size_t tokenlen, ngtcp2_encrypt encrypt, const ngtcp2_crypto_aead *aead, + const ngtcp2_crypto_aead_ctx *aead_ctx); + +/** + * @function + * + * `ngtcp2_accept` is used by server implementation, and decides + * whether packet |pkt| of length |pktlen| from client is acceptable + * for the very initial packet to a connection. + * + * If |dest| is not ``NULL`` and the function returns 0, or + * :macro:`NGTCP2_ERR_RETRY`, the decoded packet header is stored to + * the object pointed by |dest|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_RETRY` + * Retry packet should be sent. + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * The packet is not acceptable for the very first packet to a new + * connection; or the function failed to parse the packet header. + */ +NGTCP2_EXTERN int ngtcp2_accept(ngtcp2_pkt_hd *dest, const uint8_t *pkt, + size_t pktlen); + +/** + * @function + * + * `ngtcp2_conn_client_new` creates new :type:`ngtcp2_conn`, and + * initializes it as client. |dcid| is randomized destination + * connection ID. |scid| is source connection ID. + * |client_chosen_version| is a QUIC version that a client chooses. + * |path| is the network path where this QUIC connection is being + * established and must not be ``NULL``. |callbacks|, |settings|, and + * |params| must not be ``NULL``, and the function make a copy of each + * of them. |params| is local QUIC transport parameters and sent to a + * remote endpoint during handshake. |user_data| is the arbitrary + * pointer which is passed to the user-defined callback functions. If + * |mem| is ``NULL``, the memory allocator returned by + * `ngtcp2_mem_default()` is used. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_client_new_versioned( + ngtcp2_conn **pconn, const ngtcp2_cid *dcid, const ngtcp2_cid *scid, + const ngtcp2_path *path, uint32_t client_chosen_version, + int callbacks_version, const ngtcp2_callbacks *callbacks, + int settings_version, const ngtcp2_settings *settings, + int transport_params_version, const ngtcp2_transport_params *params, + const ngtcp2_mem *mem, void *user_data); + +/** + * @function + * + * `ngtcp2_conn_server_new` creates new :type:`ngtcp2_conn`, and + * initializes it as server. |dcid| is a destination connection ID. + * |scid| is a source connection ID. |path| is the network path where + * this QUIC connection is being established and must not be ``NULL``. + * |client_chosen_version| is a QUIC version that a client chooses. + * |callbacks|, |settings|, and |params| must not be ``NULL``, and the + * function make a copy of each of them. |params| is local QUIC + * transport parameters and sent to a remote endpoint during + * handshake. |user_data| is the arbitrary pointer which is passed to + * the user-defined callback functions. If |mem| is ``NULL``, the + * memory allocator returned by `ngtcp2_mem_default()` is used. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_server_new_versioned( + ngtcp2_conn **pconn, const ngtcp2_cid *dcid, const ngtcp2_cid *scid, + const ngtcp2_path *path, uint32_t client_chosen_version, + int callbacks_version, const ngtcp2_callbacks *callbacks, + int settings_version, const ngtcp2_settings *settings, + int transport_params_version, const ngtcp2_transport_params *params, + const ngtcp2_mem *mem, void *user_data); + +/** + * @function + * + * `ngtcp2_conn_del` frees resources allocated for |conn|. It also + * frees memory pointed by |conn|. + */ +NGTCP2_EXTERN void ngtcp2_conn_del(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_read_pkt` decrypts QUIC packet given in |pkt| of + * length |pktlen| and processes it. |path| is the network path the + * packet is delivered and must not be ``NULL``. |pi| is packet + * metadata and may be ``NULL``. This function performs QUIC handshake + * as well. + * + * This function must not be called from inside the callback + * functions. + * + * This function returns 0 if it succeeds, or negative error codes. + * If :macro:`NGTCP2_ERR_RETRY` is returned, application must be a + * server and it must perform address validation by sending Retry + * packet and discard the connection state. If + * :macro:`NGTCP2_ERR_DROP_CONN` is returned, server application must + * drop the connection silently (without sending any CONNECTION_CLOSE + * frame) and discard connection state. If + * :macro:`NGTCP2_ERR_DRAINING` is returned, a connection has entered + * the draining state, and no further packet transmission is allowed. + * If :macro:`NGTCP2_ERR_CRYPTO` is returned, the error happened in + * TLS stack and `ngtcp2_conn_get_tls_alert` returns TLS alert if set. + * + * If any other negative errors are returned, call + * `ngtcp2_conn_write_connection_close` to get terminal packet, and + * sending it makes QUIC connection enter the closing state. + */ +NGTCP2_EXTERN int +ngtcp2_conn_read_pkt_versioned(ngtcp2_conn *conn, const ngtcp2_path *path, + int pkt_info_version, const ngtcp2_pkt_info *pi, + const uint8_t *pkt, size_t pktlen, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_write_pkt` is equivalent to calling + * `ngtcp2_conn_writev_stream` with -1 as stream_id, no stream data, and + * :macro:`NGTCP2_WRITE_STREAM_FLAG_NONE` as flags. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_conn_write_pkt_versioned( + ngtcp2_conn *conn, ngtcp2_path *path, int pkt_info_version, + ngtcp2_pkt_info *pi, uint8_t *dest, size_t destlen, ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_handshake_completed` tells |conn| that the TLS stack + * declares TLS handshake completion. This does not mean QUIC + * handshake has completed. The library needs extra conditions to be + * met. + */ +NGTCP2_EXTERN void ngtcp2_conn_handshake_completed(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_handshake_completed` returns nonzero if QUIC handshake + * has completed. + */ +NGTCP2_EXTERN int ngtcp2_conn_get_handshake_completed(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_install_initial_key` installs packet protection keying + * materials for Initial packets. |rx_aead_ctx| is AEAD cipher + * context object and must be initialized with a decryption key. + * |rx_iv| is IV of length |rx_ivlen| for decryption. |rx_hp_ctx| is + * a packet header protection cipher context object for decryption. + * Similarly, |tx_aead_ctx|, |tx_iv| and |tx_hp_ctx| are for + * encrypting outgoing packets and are the same length with the + * decryption counterpart . If they have already been set, they are + * overwritten. + * + * |ivlen| must be the minimum length of AEAD nonce, or 8 bytes if + * that is larger. + * + * If this function succeeds, |conn| takes ownership of |rx_aead_ctx|, + * |rx_hp_ctx|, |tx_aead_ctx|, and |tx_hp_ctx|. + * :type:`ngtcp2_delete_crypto_aead_ctx` and + * :type:`ngtcp2_delete_crypto_cipher_ctx` will be called to delete + * these objects when they are no longer used. If this function + * fails, the caller is responsible to delete them. + * + * After receiving Retry packet, the DCID most likely changes. In + * that case, client application must generate these keying materials + * again based on new DCID and install them again. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_install_initial_key( + ngtcp2_conn *conn, const ngtcp2_crypto_aead_ctx *rx_aead_ctx, + const uint8_t *rx_iv, const ngtcp2_crypto_cipher_ctx *rx_hp_ctx, + const ngtcp2_crypto_aead_ctx *tx_aead_ctx, const uint8_t *tx_iv, + const ngtcp2_crypto_cipher_ctx *tx_hp_ctx, size_t ivlen); + +/** + * @function + * + * `ngtcp2_conn_install_vneg_initial_key` installs packet protection + * keying materials for Initial packets on compatible version + * negotiation for |version|. |rx_aead_ctx| is AEAD cipher context + * object and must be initialized with a decryption key. |rx_iv| is + * IV of length |rx_ivlen| for decryption. |rx_hp_ctx| is a packet + * header protection cipher context object for decryption. Similarly, + * |tx_aead_ctx|, |tx_iv| and |tx_hp_ctx| are for encrypting outgoing + * packets and are the same length with the decryption counterpart . + * If they have already been set, they are overwritten. + * + * |ivlen| must be the minimum length of AEAD nonce, or 8 bytes if + * that is larger. + * + * If this function succeeds, |conn| takes ownership of |rx_aead_ctx|, + * |rx_hp_ctx|, |tx_aead_ctx|, and |tx_hp_ctx|. + * :type:`ngtcp2_delete_crypto_aead_ctx` and + * :type:`ngtcp2_delete_crypto_cipher_ctx` will be called to delete + * these objects when they are no longer used. If this function + * fails, the caller is responsible to delete them. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_install_vneg_initial_key( + ngtcp2_conn *conn, uint32_t version, + const ngtcp2_crypto_aead_ctx *rx_aead_ctx, const uint8_t *rx_iv, + const ngtcp2_crypto_cipher_ctx *rx_hp_ctx, + const ngtcp2_crypto_aead_ctx *tx_aead_ctx, const uint8_t *tx_iv, + const ngtcp2_crypto_cipher_ctx *tx_hp_ctx, size_t ivlen); + +/** + * @function + * + * `ngtcp2_conn_install_rx_handshake_key` installs packet protection + * keying materials for decrypting incoming Handshake packets. + * |aead_ctx| is AEAD cipher context object which must be initialized + * with a decryption key. |iv| is IV of length |ivlen|. |hp_ctx| is + * a packet header protection cipher context object. + * + * |ivlen| must be the minimum length of AEAD nonce, or 8 bytes if + * that is larger. + * + * If this function succeeds, |conn| takes ownership of |aead_ctx|, + * and |hp_ctx|. :type:`ngtcp2_delete_crypto_aead_ctx` and + * :type:`ngtcp2_delete_crypto_cipher_ctx` will be called to delete + * these objects when they are no longer used. If this function + * fails, the caller is responsible to delete them. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_install_rx_handshake_key( + ngtcp2_conn *conn, const ngtcp2_crypto_aead_ctx *aead_ctx, + const uint8_t *iv, size_t ivlen, const ngtcp2_crypto_cipher_ctx *hp_ctx); + +/** + * @function + * + * `ngtcp2_conn_install_tx_handshake_key` installs packet protection + * keying materials for encrypting outgoing Handshake packets. + * |aead_ctx| is AEAD cipher context object which must be initialized + * with an encryption key. |iv| is IV of length |ivlen|. |hp_ctx| is + * a packet header protection cipher context object. + * + * |ivlen| must be the minimum length of AEAD nonce, or 8 bytes if + * that is larger. + * + * If this function succeeds, |conn| takes ownership of |aead_ctx| and + * |hp_ctx|. :type:`ngtcp2_delete_crypto_aead_ctx` and + * :type:`ngtcp2_delete_crypto_cipher_ctx` will be called to delete + * these objects when they are no longer used. If this function + * fails, the caller is responsible to delete them. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_install_tx_handshake_key( + ngtcp2_conn *conn, const ngtcp2_crypto_aead_ctx *aead_ctx, + const uint8_t *iv, size_t ivlen, const ngtcp2_crypto_cipher_ctx *hp_ctx); + +/** + * @function + * + * `ngtcp2_conn_install_early_key` installs packet protection AEAD + * cipher context object |aead_ctx|, IV |iv| of length |ivlen|, and + * packet header protection cipher context object |hp_ctx| to encrypt + * (for client) or decrypt (for server) 0RTT packets. + * + * |ivlen| must be the minimum length of AEAD nonce, or 8 bytes if + * that is larger. + * + * If this function succeeds, |conn| takes ownership of |aead_ctx| and + * |hp_ctx|. :type:`ngtcp2_delete_crypto_aead_ctx` and + * :type:`ngtcp2_delete_crypto_cipher_ctx` will be called to delete + * these objects when they are no longer used. If this function + * fails, the caller is responsible to delete them. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_install_early_key( + ngtcp2_conn *conn, const ngtcp2_crypto_aead_ctx *aead_ctx, + const uint8_t *iv, size_t ivlen, const ngtcp2_crypto_cipher_ctx *hp_ctx); + +/** + * @function + * + * `ngtcp2_conn_install_rx_key` installs packet protection keying + * materials for decrypting Short header packets. |secret| of length + * |secretlen| is the decryption secret which is used to derive keying + * materials passed to this function. |aead_ctx| is AEAD cipher + * context object which must be initialized with a decryption key. + * |iv| is IV of length |ivlen|. |hp_ctx| is a packet header + * protection cipher context object. + * + * |ivlen| must be the minimum length of AEAD nonce, or 8 bytes if + * that is larger. + * + * If this function succeeds, |conn| takes ownership of |aead_ctx| and + * |hp_ctx|. :type:`ngtcp2_delete_crypto_aead_ctx` and + * :type:`ngtcp2_delete_crypto_cipher_ctx` will be called to delete + * these objects when they are no longer used. If this function + * fails, the caller is responsible to delete them. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_install_rx_key( + ngtcp2_conn *conn, const uint8_t *secret, size_t secretlen, + const ngtcp2_crypto_aead_ctx *aead_ctx, const uint8_t *iv, size_t ivlen, + const ngtcp2_crypto_cipher_ctx *hp_ctx); + +/** + * @function + * + * `ngtcp2_conn_install_tx_key` installs packet protection keying + * materials for encrypting Short header packets. |secret| of length + * |secretlen| is the encryption secret which is used to derive keying + * materials passed to this function. |aead_ctx| is AEAD cipher + * context object which must be initialized with an encryption key. + * |iv| is IV of length |ivlen|. |hp_ctx| is a packet header + * protection cipher context object. + * + * |ivlen| must be the minimum length of AEAD nonce, or 8 bytes if + * that is larger. + * + * If this function succeeds, |conn| takes ownership of |aead_ctx| and + * |hp_ctx|. :type:`ngtcp2_delete_crypto_aead_ctx` and + * :type:`ngtcp2_delete_crypto_cipher_ctx` will be called to delete + * these objects when they are no longer used. If this function + * fails, the caller is responsible to delete them. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_install_tx_key( + ngtcp2_conn *conn, const uint8_t *secret, size_t secretlen, + const ngtcp2_crypto_aead_ctx *aead_ctx, const uint8_t *iv, size_t ivlen, + const ngtcp2_crypto_cipher_ctx *hp_ctx); + +/** + * @function + * + * `ngtcp2_conn_initiate_key_update` initiates the key update. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_INVALID_STATE` + * The previous key update has not been confirmed yet; or key + * update is too frequent; or new keys are not available yet. + */ +NGTCP2_EXTERN int ngtcp2_conn_initiate_key_update(ngtcp2_conn *conn, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_set_tls_error` sets the TLS related error |liberr| in + * |conn|. |liberr| must be one of ngtcp2 library error codes (which + * is defined as NGTCP2_ERR_* macro, such as + * :macro:`NGTCP2_ERR_DECRYPT`). In general, error code should be + * propagated via return value, but sometimes ngtcp2 API is called + * inside callback function of TLS stack and it does not allow to + * return ngtcp2 error code directly. In this case, implementation + * can set the error code (e.g., + * :macro:`NGTCP2_ERR_MALFORMED_TRANSPORT_PARAM`) using this function. + */ +NGTCP2_EXTERN void ngtcp2_conn_set_tls_error(ngtcp2_conn *conn, int liberr); + +/** + * @function + * + * `ngtcp2_conn_get_tls_error` returns the value set by + * `ngtcp2_conn_set_tls_error`. If no value is set, this function + * returns 0. + */ +NGTCP2_EXTERN int ngtcp2_conn_get_tls_error(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_tls_alert` sets a TLS alert |alert| generated by a + * local endpoint to |conn|. + */ +NGTCP2_EXTERN void ngtcp2_conn_set_tls_alert(ngtcp2_conn *conn, uint8_t alert); + +/** + * @function + * + * `ngtcp2_conn_get_tls_alert` returns the value set by + * `ngtcp2_conn_set_tls_alert`. If no value is set, this function + * returns 0. + */ +NGTCP2_EXTERN uint8_t ngtcp2_conn_get_tls_alert(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_keep_alive_timeout` sets keep-alive timeout. If + * nonzero value is given, after a connection is idle at least in a + * given amount of time, a keep-alive packet is sent. If 0 is set, + * keep-alive functionality is disabled and this is the default. + */ +NGTCP2_EXTERN void ngtcp2_conn_set_keep_alive_timeout(ngtcp2_conn *conn, + ngtcp2_duration timeout); + +/** + * @function + * + * `ngtcp2_conn_get_expiry` returns the next expiry time. It returns + * ``UINT64_MAX`` if there is no next expiry. + * + * Call `ngtcp2_conn_handle_expiry()` and `ngtcp2_conn_write_pkt` (or + * `ngtcp2_conn_writev_stream`) if expiry time is passed. + */ +NGTCP2_EXTERN ngtcp2_tstamp ngtcp2_conn_get_expiry(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_handle_expiry` handles expired timer. It does nothing + * if timer is not expired. + */ +NGTCP2_EXTERN int ngtcp2_conn_handle_expiry(ngtcp2_conn *conn, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_get_pto` returns Probe Timeout (PTO). + */ +NGTCP2_EXTERN ngtcp2_duration ngtcp2_conn_get_pto(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_decode_remote_transport_params` decodes QUIC transport + * parameters from the buffer pointed by |data| of length |datalen|, + * and sets the result to |conn|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_REQUIRED_TRANSPORT_PARAM` + * The required parameter is missing. + * :macro:`NGTCP2_ERR_MALFORMED_TRANSPORT_PARAM` + * The input is malformed. + * :macro:`NGTCP2_ERR_TRANSPORT_PARAM` + * Failed to validate the remote QUIC transport parameters. + * :macro:`NGTCP2_ERR_VERSION_NEGOTIATION_FAILURE` + * Version negotiation failure. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + */ +NGTCP2_EXTERN int +ngtcp2_conn_decode_remote_transport_params(ngtcp2_conn *conn, + const uint8_t *data, size_t datalen); + +/** + * @function + * + * `ngtcp2_conn_get_remote_transport_params` returns a pointer to the + * remote QUIC transport parameters. If no remote transport + * parameters are set, it returns NULL. + */ +NGTCP2_EXTERN const ngtcp2_transport_params * +ngtcp2_conn_get_remote_transport_params(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_early_remote_transport_params` sets |params| as + * transport parameters previously received from a server. The + * parameters are used to send early data. QUIC requires that client + * application should remember transport parameters along with a + * session ticket. + * + * At least following fields should be set: + * + * - initial_max_stream_id_bidi + * - initial_max_stream_id_uni + * - initial_max_stream_data_bidi_local + * - initial_max_stream_data_bidi_remote + * - initial_max_stream_data_uni + * - initial_max_data + * - active_connection_id_limit + * - max_datagram_frame_size (if DATAGRAM extension was negotiated) + * + * The following fields are ignored: + * + * - ack_delay_exponent + * - max_ack_delay + * - initial_scid + * - original_dcid + * - preferred_address and preferred_address_present + * - retry_scid and retry_scid_present + * - stateless_reset_token and stateless_reset_token_present + */ +NGTCP2_EXTERN void ngtcp2_conn_set_early_remote_transport_params_versioned( + ngtcp2_conn *conn, int transport_params_version, + const ngtcp2_transport_params *params); + +/** + * @function + * + * `ngtcp2_conn_set_local_transport_params` sets the local transport + * parameters |params|. This function can only be called by server. + * Although the local transport parameters are passed to + * `ngtcp2_conn_server_new`, server might want to update them after + * ALPN is chosen. In that case, server can update the transport + * parameter with this function. Server must call this function + * before calling `ngtcp2_conn_install_tx_handshake_key`. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_INVALID_STATE` + * `ngtcp2_conn_install_tx_handshake_key` has been called. + */ +NGTCP2_EXTERN int ngtcp2_conn_set_local_transport_params_versioned( + ngtcp2_conn *conn, int transport_params_version, + const ngtcp2_transport_params *params); + +/** + * @function + * + * `ngtcp2_conn_get_local_transport_params` returns a pointer to the + * local QUIC transport parameters. + */ +NGTCP2_EXTERN const ngtcp2_transport_params * +ngtcp2_conn_get_local_transport_params(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_encode_local_transport_params` encodes the local QUIC + * transport parameters in |dest| of length |destlen|. This is + * equivalent to calling `ngtcp2_conn_get_local_transport_params` and + * then `ngtcp2_encode_transport_params`. + * + * This function returns the number of written, or one of the + * following negative error codes: + * + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_conn_encode_local_transport_params( + ngtcp2_conn *conn, uint8_t *dest, size_t destlen); + +/** + * @function + * + * `ngtcp2_conn_open_bidi_stream` opens new bidirectional stream. The + * |stream_user_data| is the user data specific to the stream. The + * open stream ID is stored in |*pstream_id|. + * + * Application can call this function before handshake completes. For + * 0RTT packet, application can call this function after calling + * `ngtcp2_conn_set_early_remote_transport_params`. For 1RTT packet, + * application can call this function after calling + * `ngtcp2_conn_decode_remote_transport_params` and + * `ngtcp2_conn_install_tx_key`. If ngtcp2 crypto support library is + * used, application can call this function after calling + * `ngtcp2_crypto_derive_and_install_tx_key` for 1RTT packet. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_STREAM_ID_BLOCKED` + * The remote peer does not allow |stream_id| yet. + */ +NGTCP2_EXTERN int ngtcp2_conn_open_bidi_stream(ngtcp2_conn *conn, + int64_t *pstream_id, + void *stream_user_data); + +/** + * @function + * + * `ngtcp2_conn_open_uni_stream` opens new unidirectional stream. The + * |stream_user_data| is the user data specific to the stream. The + * open stream ID is stored in |*pstream_id|. + * + * Application can call this function before handshake completes. For + * 0RTT packet, application can call this function after calling + * `ngtcp2_conn_set_early_remote_transport_params`. For 1RTT packet, + * application can call this function after calling + * `ngtcp2_conn_decode_remote_transport_params` and + * `ngtcp2_conn_install_tx_key`. If ngtcp2 crypto support library is + * used, application can call this function after calling + * `ngtcp2_crypto_derive_and_install_tx_key` for 1RTT packet. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_STREAM_ID_BLOCKED` + * The remote peer does not allow |stream_id| yet. + */ +NGTCP2_EXTERN int ngtcp2_conn_open_uni_stream(ngtcp2_conn *conn, + int64_t *pstream_id, + void *stream_user_data); + +/** + * @function + * + * `ngtcp2_conn_shutdown_stream` closes stream denoted by |stream_id| + * abruptly. |app_error_code| is one of application error codes, and + * indicates the reason of shutdown. Successful call of this function + * does not immediately erase the state of the stream. The actual + * deletion is done when the remote endpoint sends acknowledgement. + * Calling this function is equivalent to call + * `ngtcp2_conn_shutdown_stream_read`, and + * `ngtcp2_conn_shutdown_stream_write` sequentially with the following + * differences. If |stream_id| refers to a local unidirectional + * stream, this function only shutdowns write side of the stream. If + * |stream_id| refers to a remote unidirectional stream, this function + * only shutdowns read side of the stream. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + */ +NGTCP2_EXTERN int ngtcp2_conn_shutdown_stream(ngtcp2_conn *conn, + int64_t stream_id, + uint64_t app_error_code); + +/** + * @function + * + * `ngtcp2_conn_shutdown_stream_write` closes write-side of stream + * denoted by |stream_id| abruptly. |app_error_code| is one of + * application error codes, and indicates the reason of shutdown. If + * this function succeeds, no application data is sent to the remote + * endpoint. It discards all data which has not been acknowledged + * yet. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * |stream_id| refers to a remote unidirectional stream. + */ +NGTCP2_EXTERN int ngtcp2_conn_shutdown_stream_write(ngtcp2_conn *conn, + int64_t stream_id, + uint64_t app_error_code); + +/** + * @function + * + * `ngtcp2_conn_shutdown_stream_read` closes read-side of stream + * denoted by |stream_id| abruptly. |app_error_code| is one of + * application error codes, and indicates the reason of shutdown. If + * this function succeeds, no application data is forwarded to an + * application layer. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * |stream_id| refers to a local unidirectional stream. + */ +NGTCP2_EXTERN int ngtcp2_conn_shutdown_stream_read(ngtcp2_conn *conn, + int64_t stream_id, + uint64_t app_error_code); + +/** + * @macrosection + * + * Write stream data flags + */ + +/** + * @macro + * + * :macro:`NGTCP2_WRITE_STREAM_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_WRITE_STREAM_FLAG_NONE 0x00u + +/** + * @macro + * + * :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE` indicates that more data may + * come and should be coalesced into the same packet if possible. + */ +#define NGTCP2_WRITE_STREAM_FLAG_MORE 0x01u + +/** + * @macro + * + * :macro:`NGTCP2_WRITE_STREAM_FLAG_FIN` indicates that the passed + * data is the final part of a stream. + */ +#define NGTCP2_WRITE_STREAM_FLAG_FIN 0x02u + +/** + * @function + * + * `ngtcp2_conn_write_stream` is just like + * `ngtcp2_conn_writev_stream`. The only difference is that it + * conveniently accepts a single buffer. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_conn_write_stream_versioned( + ngtcp2_conn *conn, ngtcp2_path *path, int pkt_info_version, + ngtcp2_pkt_info *pi, uint8_t *dest, size_t destlen, ngtcp2_ssize *pdatalen, + uint32_t flags, int64_t stream_id, const uint8_t *data, size_t datalen, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_writev_stream` writes a packet containing stream data + * of stream denoted by |stream_id|. The buffer of the packet is + * pointed by |dest| of length |destlen|. This function performs QUIC + * handshake as well. + * + * |destlen| should be at least + * :member:`ngtcp2_settings.max_tx_udp_payload_size`. + * + * Specifying -1 to |stream_id| means no new stream data to send. + * + * If |path| is not ``NULL``, this function stores the network path + * with which the packet should be sent. Each addr field must point + * to the buffer which should be at least ``sizeof(struct + * sockaddr_storage)`` bytes long. The assignment might not be done + * if nothing is written to |dest|. + * + * If |pi| is not ``NULL``, this function stores packet metadata in it + * if it succeeds. The metadata includes ECN markings. When calling + * this function again after it returns + * :macro:`NGTCP2_ERR_WRITE_MORE`, caller must pass the same |pi| to + * this function. + * + * If the all given data is encoded as STREAM frame in |dest|, and if + * |flags| & :macro:`NGTCP2_WRITE_STREAM_FLAG_FIN` is nonzero, fin + * flag is set to outgoing STREAM frame. Otherwise, fin flag in + * STREAM frame is not set. + * + * This packet may contain frames other than STREAM frame. The packet + * might not contain STREAM frame if other frames occupy the packet. + * In that case, |*pdatalen| would be -1 if |pdatalen| is not + * ``NULL``. + * + * If |flags| & :macro:`NGTCP2_WRITE_STREAM_FLAG_FIN` is nonzero, and + * 0 length STREAM frame is successfully serialized, |*pdatalen| would + * be 0. + * + * The number of data encoded in STREAM frame is stored in |*pdatalen| + * if it is not ``NULL``. The caller must keep the portion of data + * covered by |*pdatalen| bytes in tact until + * :type:`ngtcp2_acked_stream_data_offset` indicates that they are + * acknowledged by a remote endpoint or the stream is closed. + * + * If |flags| equals to :macro:`NGTCP2_WRITE_STREAM_FLAG_NONE`, this + * function produces a single payload of UDP packet. If the given + * stream data is small (e.g., few bytes), the packet might be + * severely under filled. Too many small packet might increase + * overall packet processing costs. Unless there are retransmissions, + * by default, application can only send 1 STREAM frame in one QUIC + * packet. In order to include more than 1 STREAM frame in one QUIC + * packet, specify :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE` in |flags|. + * This is analogous to ``MSG_MORE`` flag in :manpage:`send(2)`. If + * the :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE` is used, there are 4 + * outcomes: + * + * - The function returns the written length of packet just like + * without :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE`. This is because + * packet is nearly full and the library decided to make a complete + * packet. |*pdatalen| might be -1 or >= 0. It may return 0 which + * indicates that no packet transmission is possible at the moment + * for some reason. + * + * - The function returns :macro:`NGTCP2_ERR_WRITE_MORE`. In this + * case, |*pdatalen| >= 0 is asserted. It indicates that + * application can still call this function with different stream + * data (or `ngtcp2_conn_writev_datagram` if it has data to send in + * unreliable datagram) to pack them into the same packet. + * Application has to specify the same |conn|, |path|, |pi|, |dest|, + * |destlen|, and |ts| parameters, otherwise the behaviour is + * undefined. The application can change |flags|. + * + * - The function returns one of the following negative error codes: + * :macro:`NGTCP2_ERR_STREAM_DATA_BLOCKED`, + * :macro:`NGTCP2_ERR_STREAM_NOT_FOUND`, + * :macro:`NGTCP2_ERR_STREAM_SHUT_WR`. In this case, |*pdatalen| == + * -1 is asserted. Application can still write the stream data of + * the other streams by calling this function (or + * `ngtcp2_conn_writev_datagram` if it has data to send in + * unreliable datagram) to pack them into the same packet. + * Application has to specify the same |conn|, |path|, |pi|, |dest|, + * |destlen|, and |ts| parameters, otherwise the behaviour is + * undefined. The application can change |flags|. + * + * - The other negative error codes might be returned just like + * without :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE`. These errors + * should be treated as a connection error. + * + * When application uses :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE` at + * least once, it must not call other ngtcp2 API functions + * (application can still call `ngtcp2_conn_write_connection_close` to + * handle error from this function), just keep calling this function + * (or `ngtcp2_conn_write_pkt`, or `ngtcp2_conn_writev_datagram`) + * until it returns 0, a positive number (which indicates a complete + * packet is ready), or the error codes other than + * :macro:`NGTCP2_ERR_WRITE_MORE`, + * :macro:`NGTCP2_ERR_STREAM_DATA_BLOCKED`, + * :macro:`NGTCP2_ERR_STREAM_NOT_FOUND`, and + * :macro:`NGTCP2_ERR_STREAM_SHUT_WR`. If there is no stream data to + * include, call this function with |stream_id| as -1 to stop + * coalescing and write a packet. + * + * This function returns 0 if it cannot write any frame because buffer + * is too small, or packet is congestion limited. Application should + * keep reading and wait for congestion window to grow. + * + * This function must not be called from inside the callback + * functions. + * + * `ngtcp2_conn_update_pkt_tx_time` must be called after this + * function. Application may call this function multiple times before + * calling `ngtcp2_conn_update_pkt_tx_time`. + * + * This function returns the number of bytes written in |dest| if it + * succeeds, or one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_STREAM_NOT_FOUND` + * Stream does not exist + * :macro:`NGTCP2_ERR_STREAM_SHUT_WR` + * Stream is half closed (local); or stream is being reset. + * :macro:`NGTCP2_ERR_PKT_NUM_EXHAUSTED` + * Packet number is exhausted, and cannot send any more packet. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * The total length of stream data is too large. + * :macro:`NGTCP2_ERR_STREAM_DATA_BLOCKED` + * Stream is blocked because of flow control. + * :macro:`NGTCP2_ERR_WRITE_MORE` + * (Only when :macro:`NGTCP2_WRITE_STREAM_FLAG_MORE` is specified) + * Application can call this function to pack more stream data + * into the same packet. See above to know how it works. + * + * In general, if the error code which satisfies + * `ngtcp2_err_is_fatal(err) <ngtcp2_err_is_fatal>` != 0 is returned, + * the application should just close the connection by calling + * `ngtcp2_conn_write_connection_close` or just delete the QUIC + * connection using `ngtcp2_conn_del`. It is undefined to call the + * other library functions. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_conn_writev_stream_versioned( + ngtcp2_conn *conn, ngtcp2_path *path, int pkt_info_version, + ngtcp2_pkt_info *pi, uint8_t *dest, size_t destlen, ngtcp2_ssize *pdatalen, + uint32_t flags, int64_t stream_id, const ngtcp2_vec *datav, size_t datavcnt, + ngtcp2_tstamp ts); + +/** + * @macrosection + * + * Write datagram flags + */ + +/** + * @macro + * + * :macro:`NGTCP2_WRITE_DATAGRAM_FLAG_NONE` indicates no flag set. + */ +#define NGTCP2_WRITE_DATAGRAM_FLAG_NONE 0x00u + +/** + * @macro + * + * :macro:`NGTCP2_WRITE_DATAGRAM_FLAG_MORE` indicates that more data + * may come and should be coalesced into the same packet if possible. + */ +#define NGTCP2_WRITE_DATAGRAM_FLAG_MORE 0x01u + +/** + * @function + * + * `ngtcp2_conn_writev_datagram` writes a packet containing unreliable + * data in DATAGRAM frame. The buffer of the packet is pointed by + * |dest| of length |destlen|. This function performs QUIC handshake + * as well. + * + * |destlen| should be at least + * :member:`ngtcp2_settings.max_tx_udp_payload_size`. + * + * For |path| and |pi| parameters, refer to + * `ngtcp2_conn_writev_stream`. + * + * If the given data is written to the buffer, nonzero value is + * assigned to |*paccepted| if it is not NULL. The data in DATAGRAM + * frame cannot be fragmented; writing partial data is not possible. + * + * |dgram_id| is an opaque identifier which should uniquely identify + * the given DATAGRAM. It is passed to :type:`ngtcp2_ack_datagram` + * callback when a packet that contains DATAGRAM frame is + * acknowledged. It is passed to :type:`ngtcp2_lost_datagram` + * callback when a packet that contains DATAGRAM frame is declared + * lost. If an application uses neither of those callbacks, it can + * sets 0 to this parameter. + * + * This function might write other frames other than DATAGRAM, just + * like `ngtcp2_conn_writev_stream`. + * + * If the function returns 0, it means that no more data cannot be + * sent because of congestion control limit; or, data does not fit + * into the provided buffer; or, a local endpoint, as a server, is + * unable to send data because of its amplification limit. In this + * case, |*paccepted| is assigned zero if it is not NULL. + * + * If :macro:`NGTCP2_WRITE_DATAGRAM_FLAG_MORE` is set in |flags|, + * there are 3 outcomes: + * + * - The function returns the written length of packet just like + * without :macro:`NGTCP2_WRITE_DATAGRAM_FLAG_MORE`. This is + * because packet is nearly full and the library decided to make a + * complete packet. |*paccepted| might be zero or nonzero. + * + * - The function returns :macro:`NGTCP2_ERR_WRITE_MORE`. In this + * case, |*paccepted| != 0 is asserted. This indicates that + * application can call this function with another unreliable data + * (or `ngtcp2_conn_writev_stream` if it has stream data to send) to + * pack them into the same packet. Application has to specify the + * same |conn|, |path|, |pi|, |dest|, |destlen|, and |ts| + * parameters, otherwise the behaviour is undefined. The + * application can change |flags|. + * + * - The other error might be returned just like without + * :macro:`NGTCP2_WRITE_DATAGRAM_FLAG_MORE`. + * + * When application sees :macro:`NGTCP2_ERR_WRITE_MORE`, it must not + * call other ngtcp2 API functions (application can still call + * `ngtcp2_conn_write_connection_close` to handle error from this + * function). Just keep calling `ngtcp2_conn_writev_datagram`, + * `ngtcp2_conn_writev_stream` or `ngtcp2_conn_write_pkt` until it + * returns a positive number (which indicates a complete packet is + * ready). + * + * This function returns the number of bytes written in |dest| if it + * succeeds, or one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_PKT_NUM_EXHAUSTED` + * Packet number is exhausted, and cannot send any more packet. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + * :macro:`NGTCP2_ERR_WRITE_MORE` + * (Only when :macro:`NGTCP2_WRITE_DATAGRAM_FLAG_MORE` is + * specified) Application can call this function to pack more data + * into the same packet. See above to know how it works. + * :macro:`NGTCP2_ERR_INVALID_STATE` + * A remote endpoint did not express the DATAGRAM frame support. + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * The provisional DATAGRAM frame size exceeds the maximum + * DATAGRAM frame size that a remote endpoint can receive. + * + * In general, if the error code which satisfies + * `ngtcp2_err_is_fatal(err) <ngtcp2_err_is_fatal>` != 0 is returned, + * the application should just close the connection by calling + * `ngtcp2_conn_write_connection_close` or just delete the QUIC + * connection using `ngtcp2_conn_del`. It is undefined to call the + * other library functions. + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_conn_writev_datagram_versioned( + ngtcp2_conn *conn, ngtcp2_path *path, int pkt_info_version, + ngtcp2_pkt_info *pi, uint8_t *dest, size_t destlen, int *paccepted, + uint32_t flags, uint64_t dgram_id, const ngtcp2_vec *datav, size_t datavcnt, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_is_in_closing_period` returns nonzero if |conn| is in + * the closing period. + */ +NGTCP2_EXTERN int ngtcp2_conn_is_in_closing_period(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_is_in_draining_period` returns nonzero if |conn| is in + * the draining period. + */ +NGTCP2_EXTERN int ngtcp2_conn_is_in_draining_period(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_extend_max_stream_offset` extends stream's max stream + * data value by |datalen|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_extend_max_stream_offset(ngtcp2_conn *conn, + int64_t stream_id, + uint64_t datalen); + +/** + * @function + * + * `ngtcp2_conn_extend_max_offset` extends max data offset by + * |datalen|. + */ +NGTCP2_EXTERN void ngtcp2_conn_extend_max_offset(ngtcp2_conn *conn, + uint64_t datalen); + +/** + * @function + * + * `ngtcp2_conn_extend_max_streams_bidi` extends the number of maximum + * local bidirectional streams that a remote endpoint can open by |n|. + * + * The library does not increase maximum stream limit automatically. + * The exception is when a stream is closed without + * :type:`ngtcp2_stream_open` callback being called. In this case, + * stream limit is increased automatically. + */ +NGTCP2_EXTERN void ngtcp2_conn_extend_max_streams_bidi(ngtcp2_conn *conn, + size_t n); + +/** + * @function + * + * `ngtcp2_conn_extend_max_streams_uni` extends the number of maximum + * local unidirectional streams that a remote endpoint can open by + * |n|. + * + * The library does not increase maximum stream limit automatically. + * The exception is when a stream is closed without + * :type:`ngtcp2_stream_open` callback being called. In this case, + * stream limit is increased automatically. + */ +NGTCP2_EXTERN void ngtcp2_conn_extend_max_streams_uni(ngtcp2_conn *conn, + size_t n); + +/** + * @function + * + * `ngtcp2_conn_get_dcid` returns the non-NULL pointer to destination + * connection ID. If no destination connection ID is present, the + * return value is not ``NULL``, and its datalen field is 0. + */ +NGTCP2_EXTERN const ngtcp2_cid *ngtcp2_conn_get_dcid(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_client_initial_dcid` returns the non-NULL pointer + * to the Destination Connection ID that client sent in its Initial + * packet. + */ +NGTCP2_EXTERN const ngtcp2_cid * +ngtcp2_conn_get_client_initial_dcid(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_num_scid` returns the number of source connection + * IDs which the local endpoint has provided to the peer and have not + * retired. + */ +NGTCP2_EXTERN size_t ngtcp2_conn_get_num_scid(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_scid` writes the all source connection IDs which + * the local endpoint has provided to the peer and have not retired in + * |dest|. The buffer pointed by |dest| must have + * ``sizeof(ngtcp2_cid) * n`` bytes available, where n is the return + * value of `ngtcp2_conn_get_num_scid()`. + */ +NGTCP2_EXTERN size_t ngtcp2_conn_get_scid(ngtcp2_conn *conn, ngtcp2_cid *dest); + +/** + * @function + * + * `ngtcp2_conn_get_num_active_dcid` returns the number of the active + * destination connection ID. + */ +NGTCP2_EXTERN size_t ngtcp2_conn_get_num_active_dcid(ngtcp2_conn *conn); + +/** + * @struct + * + * :type:`ngtcp2_cid_token` is the convenient struct to store + * Connection ID, its associated path, and stateless reset token. + */ +typedef struct ngtcp2_cid_token { + /** + * :member:`seq` is the sequence number of this Connection ID. + */ + uint64_t seq; + /** + * :member:`cid` is Connection ID. + */ + ngtcp2_cid cid; + /** + * :member:`ps` is the path which is associated to this Connection + * ID. + */ + ngtcp2_path_storage ps; + /** + * :member:`token` is the stateless reset token for this Connection + * ID. + */ + uint8_t token[NGTCP2_STATELESS_RESET_TOKENLEN]; + /** + * :member:`token_present` is nonzero if token contains stateless + * reset token. + */ + uint8_t token_present; +} ngtcp2_cid_token; + +/** + * @function + * + * `ngtcp2_conn_get_active_dcid` writes the all active destination + * connection IDs and tokens to |dest|. The buffer pointed by |dest| + * must have ``sizeof(ngtcp2_cid_token) * n`` bytes available, where n + * is the return value of `ngtcp2_conn_get_num_active_dcid()`. + */ +NGTCP2_EXTERN size_t ngtcp2_conn_get_active_dcid(ngtcp2_conn *conn, + ngtcp2_cid_token *dest); + +/** + * @function + * + * `ngtcp2_conn_get_client_chosen_version` returns the client chosen + * version. + */ +NGTCP2_EXTERN uint32_t ngtcp2_conn_get_client_chosen_version(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_negotiated_version` returns the negotiated version. + * + * Until the version is negotiated, this function returns 0. + */ +NGTCP2_EXTERN uint32_t ngtcp2_conn_get_negotiated_version(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_early_data_rejected` tells |conn| that early data was + * rejected by a server, or client decided not to attempt early data + * for some reason. |conn| discards the following connection states: + * + * - Any opended streams. + * - Stream identifier allocations. + * - Max data extended by `ngtcp2_conn_extend_max_offset`. + * - Max bidi streams extended by `ngtcp2_conn_extend_max_streams_bidi`. + * - Max uni streams extended by `ngtcp2_conn_extend_max_streams_uni`. + * + * Application which wishes to retransmit early data, it has to open + * streams and send stream data again. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + */ +NGTCP2_EXTERN int ngtcp2_conn_early_data_rejected(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_early_data_rejected` returns nonzero if + * `ngtcp2_conn_early_data_rejected` has been called. + */ +NGTCP2_EXTERN int ngtcp2_conn_get_early_data_rejected(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_conn_stat` assigns connection statistics data to + * |*cstat|. + */ +NGTCP2_EXTERN void ngtcp2_conn_get_conn_stat_versioned(ngtcp2_conn *conn, + int conn_stat_version, + ngtcp2_conn_stat *cstat); + +/** + * @function + * + * `ngtcp2_conn_submit_crypto_data` submits crypto stream data |data| + * of length |datalen| to the library for transmission. The + * encryption level is given in |crypto_level|. + * + * The library makes a copy of the buffer pointed by |data| of length + * |datalen|. Application can discard |data|. + */ +NGTCP2_EXTERN int +ngtcp2_conn_submit_crypto_data(ngtcp2_conn *conn, + ngtcp2_crypto_level crypto_level, + const uint8_t *data, const size_t datalen); + +/** + * @function + * + * `ngtcp2_conn_submit_new_token` submits address validation token. + * It is sent in NEW_TOKEN frame. Only server can call this function. + * |tokenlen| must not be 0. + * + * This function makes a copy of the buffer pointed by |token| of + * length |tokenlen|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory. + */ +NGTCP2_EXTERN int ngtcp2_conn_submit_new_token(ngtcp2_conn *conn, + const uint8_t *token, + size_t tokenlen); + +/** + * @function + * + * `ngtcp2_conn_set_local_addr` sets local endpoint address |addr| to + * the current path of |conn|. + */ +NGTCP2_EXTERN void ngtcp2_conn_set_local_addr(ngtcp2_conn *conn, + const ngtcp2_addr *addr); + +/** + * @function + * + * `ngtcp2_conn_set_path_user_data` sets the |path_user_data| to the + * current path (see :member:`ngtcp2_path.user_data`). + */ +NGTCP2_EXTERN void ngtcp2_conn_set_path_user_data(ngtcp2_conn *conn, + void *path_user_data); + +/** + * @function + * + * `ngtcp2_conn_get_path` returns the current path. + */ +NGTCP2_EXTERN const ngtcp2_path *ngtcp2_conn_get_path(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_max_tx_udp_payload_size` returns the maximum UDP + * payload size that this local endpoint would send. This is the + * value of :member:`ngtcp2_settings.max_tx_udp_payload_size` that is + * passed to `ngtcp2_conn_client_new` or `ngtcp2_conn_server_new`. + */ +NGTCP2_EXTERN size_t ngtcp2_conn_get_max_tx_udp_payload_size(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_path_max_tx_udp_payload_size` returns the maximum + * UDP payload size for the current path. If + * :member:`ngtcp2_settings.no_tx_udp_payload_size_shaping` is set to + * nonzero, this function is equivalent to + * `ngtcp2_conn_get_max_tx_udp_payload_size`. Otherwise, it returns + * the maximum UDP payload size that is probed for the current path. + */ +NGTCP2_EXTERN size_t +ngtcp2_conn_get_path_max_tx_udp_payload_size(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_initiate_immediate_migration` starts connection + * migration to the given |path|. Only client can initiate migration. + * This function does immediate migration; while the path validation + * is nonetheless performed, this function does not wait for it to + * succeed. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_INVALID_STATE` + * Migration is disabled; or handshake is not yet confirmed; or + * client is migrating to server's preferred address. + * :macro:`NGTCP2_ERR_CONN_ID_BLOCKED` + * No unused connection ID is available. + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * |local_addr| equals the current local address. + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + */ +NGTCP2_EXTERN int ngtcp2_conn_initiate_immediate_migration( + ngtcp2_conn *conn, const ngtcp2_path *path, ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_initiate_migration` starts connection migration to the + * given |path|. Only client can initiate migration. Unlike + * `ngtcp2_conn_initiate_immediate_migration`, this function starts a + * path validation with a new path and migrate to the new path after + * successful path validation. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_INVALID_STATE` + * Migration is disabled; or handshake is not yet confirmed; or + * client is migrating to server's preferred address. + * :macro:`NGTCP2_ERR_CONN_ID_BLOCKED` + * No unused connection ID is available. + * :macro:`NGTCP2_ERR_INVALID_ARGUMENT` + * |local_addr| equals the current local address. + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + */ +NGTCP2_EXTERN int ngtcp2_conn_initiate_migration(ngtcp2_conn *conn, + const ngtcp2_path *path, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_get_max_local_streams_uni` returns the cumulative + * number of streams which local endpoint can open. + */ +NGTCP2_EXTERN uint64_t ngtcp2_conn_get_max_local_streams_uni(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_max_data_left` returns the number of bytes that + * this local endpoint can send in this connection. + */ +NGTCP2_EXTERN uint64_t ngtcp2_conn_get_max_data_left(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_max_stream_data_left` returns the number of bytes + * that this local endpoint can send to a stream identified by + * |stream_id|. If no such stream is found, this function returns 0. + */ +NGTCP2_EXTERN uint64_t ngtcp2_conn_get_max_stream_data_left(ngtcp2_conn *conn, + int64_t stream_id); + +/** + * @function + * + * `ngtcp2_conn_get_streams_bidi_left` returns the number of + * bidirectional streams which the local endpoint can open without + * violating stream concurrency limit. + */ +NGTCP2_EXTERN uint64_t ngtcp2_conn_get_streams_bidi_left(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_streams_uni_left` returns the number of + * unidirectional streams which the local endpoint can open without + * violating stream concurrency limit. + */ +NGTCP2_EXTERN uint64_t ngtcp2_conn_get_streams_uni_left(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_cwnd_left` returns the cwnd minus the number of + * bytes in flight on the current path. If the former is smaller than + * the latter, this function returns 0. + */ +NGTCP2_EXTERN uint64_t ngtcp2_conn_get_cwnd_left(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_initial_crypto_ctx` sets |ctx| for Initial packet + * encryption. The passed data will be passed to + * :type:`ngtcp2_encrypt`, :type:`ngtcp2_decrypt` and + * :type:`ngtcp2_hp_mask` callbacks. + */ +NGTCP2_EXTERN void +ngtcp2_conn_set_initial_crypto_ctx(ngtcp2_conn *conn, + const ngtcp2_crypto_ctx *ctx); + +/** + * @function + * + * `ngtcp2_conn_get_initial_crypto_ctx` returns + * :type:`ngtcp2_crypto_ctx` object for Initial packet encryption. + */ +NGTCP2_EXTERN const ngtcp2_crypto_ctx * +ngtcp2_conn_get_initial_crypto_ctx(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_crypto_ctx` sets |ctx| for Handshake/1RTT packet + * encryption. The passed data will be passed to + * :type:`ngtcp2_encrypt`, :type:`ngtcp2_decrypt` and + * :type:`ngtcp2_hp_mask` callbacks. + */ +NGTCP2_EXTERN void ngtcp2_conn_set_crypto_ctx(ngtcp2_conn *conn, + const ngtcp2_crypto_ctx *ctx); + +/** + * @function + * + * `ngtcp2_conn_get_tls_native_handle` returns TLS native handle set by + * `ngtcp2_conn_set_tls_native_handle()`. + */ +NGTCP2_EXTERN void *ngtcp2_conn_get_tls_native_handle(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_tls_native_handle` sets TLS native handle + * |tls_native_handle| to |conn|. Internally, it is used as an opaque + * pointer. + */ +NGTCP2_EXTERN void ngtcp2_conn_set_tls_native_handle(ngtcp2_conn *conn, + void *tls_native_handle); + +/** + * @function + * + * `ngtcp2_conn_set_retry_aead` sets |aead| and |aead_ctx| for Retry + * integrity tag verification. |aead| must be AEAD_AES_128_GCM. + * |aead_ctx| must be initialized with :macro:`NGTCP2_RETRY_KEY` as + * encryption key. This function must be called if |conn| is + * initialized as client. Server does not verify the tag and has no + * need to call this function. + * + * If this function succeeds, |conn| takes ownership of |aead_ctx|. + * :type:`ngtcp2_delete_crypto_aead_ctx` will be called to delete this + * object when it is no longer used. If this function fails, the + * caller is responsible to delete it. + */ +NGTCP2_EXTERN void +ngtcp2_conn_set_retry_aead(ngtcp2_conn *conn, const ngtcp2_crypto_aead *aead, + const ngtcp2_crypto_aead_ctx *aead_ctx); + +/** + * @function + * + * `ngtcp2_conn_get_crypto_ctx` returns :type:`ngtcp2_crypto_ctx` + * object for Handshake/1RTT packet encryption. + */ +NGTCP2_EXTERN const ngtcp2_crypto_ctx * +ngtcp2_conn_get_crypto_ctx(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_early_crypto_ctx` sets |ctx| for 0RTT packet + * encryption. The passed data will be passed to + * :type:`ngtcp2_encrypt`, :type:`ngtcp2_decrypt` and + * :type:`ngtcp2_hp_mask` callbacks. + */ +NGTCP2_EXTERN void +ngtcp2_conn_set_early_crypto_ctx(ngtcp2_conn *conn, + const ngtcp2_crypto_ctx *ctx); + +/** + * @function + * + * `ngtcp2_conn_get_early_crypto_ctx` returns + * :type:`ngtcp2_crypto_ctx` object for 0RTT packet encryption. + */ +NGTCP2_EXTERN const ngtcp2_crypto_ctx * +ngtcp2_conn_get_early_crypto_ctx(ngtcp2_conn *conn); + +/** + * @enum + * + * :type:`ngtcp2_connection_close_error_code_type` defines connection + * error code type. + */ +typedef enum ngtcp2_connection_close_error_code_type { + /** + * :enum:`NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT` + * indicates the error code is QUIC transport error code. + */ + NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT, + /** + * :enum:`NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_APPLICATION` + * indicates the error code is application error code. + */ + NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_APPLICATION, + /** + * :enum:`NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT_VERSION_NEGOTIATION` + * is a special case of QUIC transport error, and it indicates that + * client receives Version Negotiation packet. + */ + NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT_VERSION_NEGOTIATION, + /** + * :enum:`NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT_IDLE_CLOSE` + * is a special case of QUIC transport error, and it indicates that + * connection is closed because of idle timeout. + */ + NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT_IDLE_CLOSE +} ngtcp2_connection_close_error_code_type; + +/** + * @struct + * + * :type:`ngtcp2_connection_close_error` contains connection + * error code, its type, and the optional reason phrase. + */ +typedef struct ngtcp2_connection_close_error { + /** + * :member:`type` is the type of :member:`error_code`. + */ + ngtcp2_connection_close_error_code_type type; + /** + * :member:`error_code` is the error code for connection closure. + */ + uint64_t error_code; + /** + * :member:`frame_type` is the type of QUIC frame which triggers + * this connection error. This field is set to 0 if the frame type + * is unknown. + */ + uint64_t frame_type; + /** + * :member:`reason` points to the buffer which contains a reason + * phrase. It may be NULL if there is no reason phrase. If it is + * received from a remote endpoint, it is truncated to at most 1024 + * bytes. + */ + const uint8_t *reason; + /** + * :member:`reasonlen` is the length of data pointed by + * :member:`reason`. + */ + size_t reasonlen; +} ngtcp2_connection_close_error; + +/** + * @function + * + * `ngtcp2_connection_close_error_default` initializes |ccerr| with + * the default values. It sets the following fields: + * + * - :member:`type <ngtcp2_connection_close_error.type>` = + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT` + * - :member:`error_code <ngtcp2_connection_close_error.error_code>` = + * :macro:`NGTCP2_NO_ERROR`. + * - :member:`frame_type <ngtcp2_connection_close_error.frame_type>` = + * 0 + * - :member:`reason <ngtcp2_connection_close_error.reason>` = NULL + * - :member:`reasonlen <ngtcp2_connection_close_error.reasonlen>` = 0 + */ +NGTCP2_EXTERN void +ngtcp2_connection_close_error_default(ngtcp2_connection_close_error *ccerr); + +/** + * @function + * + * `ngtcp2_connection_close_error_set_transport_error` sets + * :member:`ccerr->type <ngtcp2_connection_close_error.type>` to + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT`, + * and :member:`ccerr->error_code + * <ngtcp2_connection_close_error.error_code>` to |error_code|. + * |reason| is the reason phrase of length |reasonlen|. This function + * does not make a copy of the reason phrase. + */ +NGTCP2_EXTERN void ngtcp2_connection_close_error_set_transport_error( + ngtcp2_connection_close_error *ccerr, uint64_t error_code, + const uint8_t *reason, size_t reasonlen); + +/** + * @function + * + * `ngtcp2_connection_close_error_set_transport_error_liberr` sets + * type and error_code based on |liberr|. + * + * If |liberr| is :macro:`NGTCP2_ERR_RECV_VERSION_NEGOTIATION`, + * :member:`ccerr->type <ngtcp2_connection_close_error.type>` is set + * to + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT_VERSION_NEGOTIATION`, + * and :member:`ccerr->error_code + * <ngtcp2_connection_close_error.error_code>` to + * :macro:`NGTCP2_NO_ERROR`. If |liberr| is + * :macro:`NGTCP2_ERR_IDLE_CLOSE`, :member:`ccerr->type + * <ngtcp2_connection_close_error.type>` is set to + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT_IDLE_CLOSE`, + * and :member:`ccerr->error_code + * <ngtcp2_connection_close_error.error_code>` to + * :macro:`NGTCP2_NO_ERROR`. Otherwise, :member:`ccerr->type + * <ngtcp2_connection_close_error.type>` is set to + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT`, + * and :member:`ccerr->error_code + * <ngtcp2_connection_close_error.error_code>` is set to an error code + * inferred by |liberr| (see + * `ngtcp2_err_infer_quic_transport_error_code`). |reason| is the + * reason phrase of length |reasonlen|. This function does not make a + * copy of the reason phrase. + */ +NGTCP2_EXTERN void ngtcp2_connection_close_error_set_transport_error_liberr( + ngtcp2_connection_close_error *ccerr, int liberr, const uint8_t *reason, + size_t reasonlen); + +/** + * @function + * + * `ngtcp2_connection_close_error_set_transport_error_tls_alert` sets + * :member:`ccerr->type <ngtcp2_connection_close_error.type>` to + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT`, + * and :member:`ccerr->error_code + * <ngtcp2_connection_close_error.error_code>` to bitwise-OR of + * :macro:`NGTCP2_CRYPTO_ERROR` and |tls_alert|. |reason| is the + * reason phrase of length |reasonlen|. This function does not make a + * copy of the reason phrase. + */ +NGTCP2_EXTERN void ngtcp2_connection_close_error_set_transport_error_tls_alert( + ngtcp2_connection_close_error *ccerr, uint8_t tls_alert, + const uint8_t *reason, size_t reasonlen); + +/** + * @function + * + * `ngtcp2_connection_close_error_set_application_error` sets + * :member:`ccerr->type <ngtcp2_connection_close_error.type>` to + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_APPLICATION`, + * and :member:`ccerr->error_code + * <ngtcp2_connection_close_error.error_code>` to |error_code|. + * |reason| is the reason phrase of length |reasonlen|. This function + * does not make a copy of the reason phrase. + */ +NGTCP2_EXTERN void ngtcp2_connection_close_error_set_application_error( + ngtcp2_connection_close_error *ccerr, uint64_t error_code, + const uint8_t *reason, size_t reasonlen); + +/** + * @function + * + * `ngtcp2_conn_write_connection_close` writes a packet which contains + * CONNECTION_CLOSE frame(s) (type 0x1c or 0x1d) in the buffer pointed + * by |dest| whose capacity is |destlen|. + * + * For client, |destlen| should be at least + * :macro:`NGTCP2_MAX_UDP_PAYLOAD_SIZE`. + * + * If |path| is not ``NULL``, this function stores the network path + * with which the packet should be sent. Each addr field must point + * to the buffer which should be at least ``sizeof(struct + * sockaddr_storage)`` bytes long. The assignment might not be done + * if nothing is written to |dest|. + * + * If |pi| is not ``NULL``, this function stores packet metadata in it + * if it succeeds. The metadata includes ECN markings. + * + * If :member:`ccerr->type <ngtcp2_connection_close_error.type>` == + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_TRANSPORT`, + * this function sends CONNECTION_CLOSE (type 0x1c) frame. If + * :member:`ccerr->type <ngtcp2_connection_close_error.type>` == + * :enum:`ngtcp2_connection_close_error_code_type.NGTCP2_CONNECTION_CLOSE_ERROR_CODE_TYPE_APPLICATION`, + * it sends CONNECTION_CLOSE (type 0x1d) frame. Otherwise, it does + * not produce any data, and returns 0. + * + * This function must not be called from inside the callback + * functions. + * + * At the moment, successful call to this function makes connection + * close. We may change this behaviour in the future to allow + * graceful shutdown. + * + * This function returns the number of bytes written in |dest| if it + * succeeds, or one of the following negative error codes: + * + * :macro:`NGTCP2_ERR_NOMEM` + * Out of memory + * :macro:`NGTCP2_ERR_NOBUF` + * Buffer is too small + * :macro:`NGTCP2_ERR_INVALID_STATE` + * The current state does not allow sending CONNECTION_CLOSE. + * :macro:`NGTCP2_ERR_PKT_NUM_EXHAUSTED` + * Packet number is exhausted, and cannot send any more packet. + * :macro:`NGTCP2_ERR_CALLBACK_FAILURE` + * User callback failed + */ +NGTCP2_EXTERN ngtcp2_ssize ngtcp2_conn_write_connection_close_versioned( + ngtcp2_conn *conn, ngtcp2_path *path, int pkt_info_version, + ngtcp2_pkt_info *pi, uint8_t *dest, size_t destlen, + const ngtcp2_connection_close_error *ccerr, ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_get_connection_close_error` stores the received + * connection close error in |ccerr|. + */ +NGTCP2_EXTERN void +ngtcp2_conn_get_connection_close_error(ngtcp2_conn *conn, + ngtcp2_connection_close_error *ccerr); + +/** + * @function + * + * `ngtcp2_conn_is_local_stream` returns nonzero if |stream_id| denotes the + * stream which a local endpoint issues. + */ +NGTCP2_EXTERN int ngtcp2_conn_is_local_stream(ngtcp2_conn *conn, + int64_t stream_id); + +/** + * @function + * + * `ngtcp2_conn_is_server` returns nonzero if |conn| is initialized as + * server. + */ +NGTCP2_EXTERN int ngtcp2_conn_is_server(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_after_retry` returns nonzero if |conn| as a client has + * received Retry packet from server and successfully validated it. + */ +NGTCP2_EXTERN int ngtcp2_conn_after_retry(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_set_stream_user_data` sets |stream_user_data| to the + * stream identified by |stream_id|. + * + * This function returns 0 if it succeeds, or one of the following + * negative error codes: + * + * :macro:`NGTCP2_ERR_STREAM_NOT_FOUND` + * Stream does not exist + */ +NGTCP2_EXTERN int ngtcp2_conn_set_stream_user_data(ngtcp2_conn *conn, + int64_t stream_id, + void *stream_user_data); + +/** + * @function + * + * `ngtcp2_conn_update_pkt_tx_time` sets the time instant of the next + * packet transmission. This function must be called after (multiple + * invocation of) `ngtcp2_conn_writev_stream`. If packet aggregation + * (e.g., packet batching, GSO) is used, call this function after all + * aggregated datagrams are sent, which indicates multiple invocation + * of `ngtcp2_conn_writev_stream`. + */ +NGTCP2_EXTERN void ngtcp2_conn_update_pkt_tx_time(ngtcp2_conn *conn, + ngtcp2_tstamp ts); + +/** + * @function + * + * `ngtcp2_conn_get_send_quantum` returns the maximum number of bytes + * that can be sent in one go without packet spacing. + */ +NGTCP2_EXTERN size_t ngtcp2_conn_get_send_quantum(ngtcp2_conn *conn); + +/** + * @function + * + * `ngtcp2_conn_get_stream_loss_count` returns the number of packets + * that contain STREAM frame for a stream identified by |stream_id| + * and are declared to be lost. The number may include the spurious + * losses. If no stream identified by |stream_id| is found, this + * function returns 0. + */ +NGTCP2_EXTERN size_t ngtcp2_conn_get_stream_loss_count(ngtcp2_conn *conn, + int64_t stream_id); + +/** + * @function + * + * `ngtcp2_strerror` returns the text representation of |liberr|. + * |liberr| must be one of ngtcp2 library error codes (which is + * defined as NGTCP2_ERR_* macro, such as + * :macro:`NGTCP2_ERR_DECRYPT`). + */ +NGTCP2_EXTERN const char *ngtcp2_strerror(int liberr); + +/** + * @function + * + * `ngtcp2_err_is_fatal` returns nonzero if |liberr| is a fatal error. + * |liberr| must be one of ngtcp2 library error codes (which is + * defined as NGTCP2_ERR_* macro, such as + * :macro:`NGTCP2_ERR_DECRYPT`). + */ +NGTCP2_EXTERN int ngtcp2_err_is_fatal(int liberr); + +/** + * @function + * + * `ngtcp2_err_infer_quic_transport_error_code` returns a QUIC + * transport error code which corresponds to |liberr|. |liberr| must + * be one of ngtcp2 library error codes (which is defined as + * NGTCP2_ERR_* macro, such as :macro:`NGTCP2_ERR_DECRYPT`). + */ +NGTCP2_EXTERN uint64_t ngtcp2_err_infer_quic_transport_error_code(int liberr); + +/** + * @function + * + * `ngtcp2_addr_init` initializes |dest| with the given arguments and + * returns |dest|. + */ +NGTCP2_EXTERN ngtcp2_addr *ngtcp2_addr_init(ngtcp2_addr *dest, + const ngtcp2_sockaddr *addr, + ngtcp2_socklen addrlen); + +/** + * @function + * + * `ngtcp2_addr_copy_byte` copies |addr| of length |addrlen| into the + * buffer pointed by :member:`dest->addr <ngtcp2_addr.addr>`. + * :member:`dest->addrlen <ngtcp2_addr.addrlen>` is updated to have + * |addrlen|. This function assumes that :member:`dest->addr + * <ngtcp2_addr.addr>` points to a buffer which has a sufficient + * capacity to store the copy. + */ +NGTCP2_EXTERN void ngtcp2_addr_copy_byte(ngtcp2_addr *dest, + const ngtcp2_sockaddr *addr, + ngtcp2_socklen addrlen); + +/** + * @function + * + * `ngtcp2_path_storage_init` initializes |ps| with the given + * arguments. This function copies |local_addr| and |remote_addr|. + */ +NGTCP2_EXTERN void ngtcp2_path_storage_init(ngtcp2_path_storage *ps, + const ngtcp2_sockaddr *local_addr, + ngtcp2_socklen local_addrlen, + const ngtcp2_sockaddr *remote_addr, + ngtcp2_socklen remote_addrlen, + void *user_data); + +/** + * @function + * + * `ngtcp2_path_storage_zero` initializes |ps| with the zero length + * addresses. + */ +NGTCP2_EXTERN void ngtcp2_path_storage_zero(ngtcp2_path_storage *ps); + +/** + * @function + * + * `ngtcp2_settings_default` initializes |settings| with the default + * values. First this function fills |settings| with 0 and set the + * default value to the following fields: + * + * * :type:`cc_algo <ngtcp2_settings.cc_algo>` = + * :enum:`ngtcp2_cc_algo.NGTCP2_CC_ALGO_CUBIC` + * * :type:`initial_rtt <ngtcp2_settings.initial_rtt>` = + * :macro:`NGTCP2_DEFAULT_INITIAL_RTT` + * * :type:`ack_thresh <ngtcp2_settings.ack_thresh>` = 2 + * * :type:`max_tx_udp_payload_size + * <ngtcp2_settings.max_tx_udp_payload_size>` = 1452 + * * :type:`handshake_timeout <ngtcp2_settings.handshake_timeout>` = + * :macro:`NGTCP2_DEFAULT_HANDSHAKE_TIMEOUT`. + */ +NGTCP2_EXTERN void ngtcp2_settings_default_versioned(int settings_version, + ngtcp2_settings *settings); + +/** + * @function + * + * `ngtcp2_transport_params_default` initializes |params| with the + * default values. First this function fills |params| with 0 and set + * the default value to the following fields: + * + * * :type:`max_udp_payload_size + * <ngtcp2_transport_params.max_udp_payload_size>` = + * :macro:`NGTCP2_DEFAULT_MAX_RECV_UDP_PAYLOAD_SIZE` + * * :type:`ack_delay_exponent + * <ngtcp2_transport_params.ack_delay_exponent>` = + * :macro:`NGTCP2_DEFAULT_ACK_DELAY_EXPONENT` + * * :type:`max_ack_delay <ngtcp2_transport_params.max_ack_delay>` = + * :macro:`NGTCP2_DEFAULT_MAX_ACK_DELAY` + * * :type:`active_connection_id_limit + * <ngtcp2_transport_params.active_connection_id_limit>` = + * :macro:`NGTCP2_DEFAULT_ACTIVE_CONNECTION_ID_LIMIT` + */ +NGTCP2_EXTERN void +ngtcp2_transport_params_default_versioned(int transport_params_version, + ngtcp2_transport_params *params); + +/** + * @function + * + * `ngtcp2_mem_default` returns the default, system standard memory + * allocator. + */ +NGTCP2_EXTERN const ngtcp2_mem *ngtcp2_mem_default(void); + +/** + * @macrosection + * + * ngtcp2_info macros + */ + +/** + * @macro + * + * :macro:`NGTCP2_VERSION_AGE` is the age of :type:`ngtcp2_info` + */ +#define NGTCP2_VERSION_AGE 1 + +/** + * @struct + * + * :type:`ngtcp2_info` is what `ngtcp2_version()` returns. It holds + * information about the particular ngtcp2 version. + */ +typedef struct ngtcp2_info { + /** + * :member:`age` is the age of this struct. This instance of ngtcp2 + * sets it to :macro:`NGTCP2_VERSION_AGE` but a future version may + * bump it and add more struct fields at the bottom + */ + int age; + /** + * :member:`version_num` is the :macro:`NGTCP2_VERSION_NUM` number + * (since age ==1) + */ + int version_num; + /** + * :member:`version_str` points to the :macro:`NGTCP2_VERSION` + * string (since age ==1) + */ + const char *version_str; + /* -------- the above fields all exist when age == 1 */ +} ngtcp2_info; + +/** + * @function + * + * `ngtcp2_version` returns a pointer to a ngtcp2_info struct with + * version information about the run-time library in use. The + * |least_version| argument can be set to a 24 bit numerical value for + * the least accepted version number and if the condition is not met, + * this function will return a ``NULL``. Pass in 0 to skip the + * version checking. + */ +NGTCP2_EXTERN const ngtcp2_info *ngtcp2_version(int least_version); + +/** + * @function + * + * `ngtcp2_is_bidi_stream` returns nonzero if |stream_id| denotes + * bidirectional stream. + */ +NGTCP2_EXTERN int ngtcp2_is_bidi_stream(int64_t stream_id); + +/** + * @function + * + * `ngtcp2_path_copy` copies |src| into |dest|. This function assumes + * that |dest| has enough buffer to store the deep copy of + * :member:`src->local <ngtcp2_path.local>` and :member:`src->remote + * <ngtcp2_path.remote>`. + */ +NGTCP2_EXTERN void ngtcp2_path_copy(ngtcp2_path *dest, const ngtcp2_path *src); + +/** + * @function + * + * `ngtcp2_path_eq` returns nonzero if |a| and |b| shares the same + * local and remote addresses. + */ +NGTCP2_EXTERN int ngtcp2_path_eq(const ngtcp2_path *a, const ngtcp2_path *b); + +/** + * @function + * + * `ngtcp2_is_supported_version` returns nonzero if the library supports + * QUIC version |version|. + */ +NGTCP2_EXTERN int ngtcp2_is_supported_version(uint32_t version); + +/* + * @function + * + * `ngtcp2_is_reserved_version` returns nonzero if |version| is a + * reserved version. + */ +NGTCP2_EXTERN int ngtcp2_is_reserved_version(uint32_t version); + +/** + * @function + * + * `ngtcp2_select_version` selects and returns a version from the + * version set |offered_versions| of |offered_versionslen| elements. + * |preferred_versions| of |preferred_versionslen| elements specifies + * the preference of versions, which is sorted in the order of + * preference. All versions included in |preferred_versions| must be + * supported by the library, that is, passing a version to + * `ngtcp2_is_supported_version` must return nonzero. This function + * is intended to be used by client when it receives Version + * Negotiation packet. If no version is selected, this function + * returns 0. + */ +NGTCP2_EXTERN uint32_t ngtcp2_select_version(const uint32_t *preferred_versions, + size_t preferred_versionslen, + const uint32_t *offered_versions, + size_t offered_versionslen); + +/* + * Versioned function wrappers + */ + +/* + * `ngtcp2_conn_read_pkt` is a wrapper around + * `ngtcp2_conn_read_pkt_versioned` to set the correct struct version. + */ +#define ngtcp2_conn_read_pkt(CONN, PATH, PI, PKT, PKTLEN, TS) \ + ngtcp2_conn_read_pkt_versioned((CONN), (PATH), NGTCP2_PKT_INFO_VERSION, \ + (PI), (PKT), (PKTLEN), (TS)) + +/* + * `ngtcp2_conn_write_pkt` is a wrapper around + * `ngtcp2_conn_write_pkt_versioned` to set the correct struct + * version. + */ +#define ngtcp2_conn_write_pkt(CONN, PATH, PI, DEST, DESTLEN, TS) \ + ngtcp2_conn_write_pkt_versioned((CONN), (PATH), NGTCP2_PKT_INFO_VERSION, \ + (PI), (DEST), (DESTLEN), (TS)) + +/* + * `ngtcp2_conn_write_stream` is a wrapper around + * `ngtcp2_conn_write_stream_versioned` to set the correct struct + * version. + */ +#define ngtcp2_conn_write_stream(CONN, PATH, PI, DEST, DESTLEN, PDATALEN, \ + FLAGS, STREAM_ID, DATA, DATALEN, TS) \ + ngtcp2_conn_write_stream_versioned( \ + (CONN), (PATH), NGTCP2_PKT_INFO_VERSION, (PI), (DEST), (DESTLEN), \ + (PDATALEN), (FLAGS), (STREAM_ID), (DATA), (DATALEN), (TS)) + +/* + * `ngtcp2_conn_writev_stream` is a wrapper around + * `ngtcp2_conn_writev_stream_versioned` to set the correct struct + * version. + */ +#define ngtcp2_conn_writev_stream(CONN, PATH, PI, DEST, DESTLEN, PDATALEN, \ + FLAGS, STREAM_ID, DATAV, DATAVCNT, TS) \ + ngtcp2_conn_writev_stream_versioned( \ + (CONN), (PATH), NGTCP2_PKT_INFO_VERSION, (PI), (DEST), (DESTLEN), \ + (PDATALEN), (FLAGS), (STREAM_ID), (DATAV), (DATAVCNT), (TS)) + +/* + * `ngtcp2_conn_writev_datagram` is a wrapper around + * `ngtcp2_conn_writev_datagram_versioned` to set the correct struct + * version. + */ +#define ngtcp2_conn_writev_datagram(CONN, PATH, PI, DEST, DESTLEN, PACCEPTED, \ + FLAGS, DGRAM_ID, DATAV, DATAVCNT, TS) \ + ngtcp2_conn_writev_datagram_versioned( \ + (CONN), (PATH), NGTCP2_PKT_INFO_VERSION, (PI), (DEST), (DESTLEN), \ + (PACCEPTED), (FLAGS), (DGRAM_ID), (DATAV), (DATAVCNT), (TS)) + +/* + * `ngtcp2_conn_write_connection_close` is a wrapper around + * `ngtcp2_conn_write_connection_close_versioned` to set the correct + * struct version. + */ +#define ngtcp2_conn_write_connection_close(CONN, PATH, PI, DEST, DESTLEN, \ + CCERR, TS) \ + ngtcp2_conn_write_connection_close_versioned( \ + (CONN), (PATH), NGTCP2_PKT_INFO_VERSION, (PI), (DEST), (DESTLEN), \ + (CCERR), (TS)) + +/* + * `ngtcp2_encode_transport_params` is a wrapper around + * `ngtcp2_encode_transport_params_versioned` to set the correct + * struct version. + */ +#define ngtcp2_encode_transport_params(DEST, DESTLEN, EXTTYPE, PARAMS) \ + ngtcp2_encode_transport_params_versioned( \ + (DEST), (DESTLEN), (EXTTYPE), NGTCP2_TRANSPORT_PARAMS_VERSION, (PARAMS)) + +/* + * `ngtcp2_decode_transport_params` is a wrapper around + * `ngtcp2_decode_transport_params_versioned` to set the correct + * struct version. + */ +#define ngtcp2_decode_transport_params(PARAMS, EXTTYPE, DATA, DATALEN) \ + ngtcp2_decode_transport_params_versioned( \ + NGTCP2_TRANSPORT_PARAMS_VERSION, (PARAMS), (EXTTYPE), (DATA), (DATALEN)) + +/* + * `ngtcp2_conn_client_new` is a wrapper around + * `ngtcp2_conn_client_new_versioned` to set the correct struct + * version. + */ +#define ngtcp2_conn_client_new(PCONN, DCID, SCID, PATH, VERSION, CALLBACKS, \ + SETTINGS, PARAMS, MEM, USER_DATA) \ + ngtcp2_conn_client_new_versioned( \ + (PCONN), (DCID), (SCID), (PATH), (VERSION), NGTCP2_CALLBACKS_VERSION, \ + (CALLBACKS), NGTCP2_SETTINGS_VERSION, (SETTINGS), \ + NGTCP2_TRANSPORT_PARAMS_VERSION, (PARAMS), (MEM), (USER_DATA)) + +/* + * `ngtcp2_conn_server_new` is a wrapper around + * `ngtcp2_conn_server_new_versioned` to set the correct struct + * version. + */ +#define ngtcp2_conn_server_new(PCONN, DCID, SCID, PATH, VERSION, CALLBACKS, \ + SETTINGS, PARAMS, MEM, USER_DATA) \ + ngtcp2_conn_server_new_versioned( \ + (PCONN), (DCID), (SCID), (PATH), (VERSION), NGTCP2_CALLBACKS_VERSION, \ + (CALLBACKS), NGTCP2_SETTINGS_VERSION, (SETTINGS), \ + NGTCP2_TRANSPORT_PARAMS_VERSION, (PARAMS), (MEM), (USER_DATA)) + +/* + * `ngtcp2_conn_set_early_remote_transport_params` is a wrapper around + * `ngtcp2_conn_set_early_remote_transport_params_versioned` to set + * the correct struct version. + */ +#define ngtcp2_conn_set_early_remote_transport_params(CONN, PARAMS) \ + ngtcp2_conn_set_early_remote_transport_params_versioned( \ + (CONN), NGTCP2_TRANSPORT_PARAMS_VERSION, (PARAMS)) + +/* + * `ngtcp2_conn_set_local_transport_params` is a wrapper around + * `ngtcp2_conn_set_local_transport_params_versioned` to set the + * correct struct version. + */ +#define ngtcp2_conn_set_local_transport_params(CONN, PARAMS) \ + ngtcp2_conn_set_local_transport_params_versioned( \ + (CONN), NGTCP2_TRANSPORT_PARAMS_VERSION, (PARAMS)) + +/* + * `ngtcp2_transport_params_default` is a wrapper around + * `ngtcp2_transport_params_default_versioned` to set the correct + * struct version. + */ +#define ngtcp2_transport_params_default(PARAMS) \ + ngtcp2_transport_params_default_versioned(NGTCP2_TRANSPORT_PARAMS_VERSION, \ + (PARAMS)) + +/* + * `ngtcp2_conn_get_conn_stat` is a wrapper around + * `ngtcp2_conn_get_conn_stat_versioned` to set the correct struct + * version. + */ +#define ngtcp2_conn_get_conn_stat(CONN, CSTAT) \ + ngtcp2_conn_get_conn_stat_versioned((CONN), NGTCP2_CONN_STAT_VERSION, (CSTAT)) + +/* + * `ngtcp2_settings_default` is a wrapper around + * `ngtcp2_settings_default_versioned` to set the correct struct + * version. + */ +#define ngtcp2_settings_default(SETTINGS) \ + ngtcp2_settings_default_versioned(NGTCP2_SETTINGS_VERSION, (SETTINGS)) + +#ifdef _MSC_VER +# pragma warning(pop) +#endif + +#ifdef __cplusplus +} +#endif + +#endif /* NGTCP2_H */ |